memory: add owner argument to initialization functions

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

313 files changed, 740 insertions, 739 deletions

diff --git a/hw/acpi/core.c b/hw/acpi/core.c
index 42eeace6f6..7206e9c69b 100644
--- a/hw/acpi/core.c
+++ b/hw/acpi/core.c
@@ -419,7 +419,7 @@ void acpi_pm1_evt_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
                        MemoryRegion *parent)
 {
     ar->pm1.evt.update_sci = update_sci;
-    memory_region_init_io(&ar->pm1.evt.io, &acpi_pm_evt_ops, ar, "acpi-evt", 4);
+    memory_region_init_io(&ar->pm1.evt.io, NULL, &acpi_pm_evt_ops, ar, "acpi-evt", 4);
     memory_region_add_subregion(parent, 0, &ar->pm1.evt.io);
 }
 
@@ -481,7 +481,7 @@ void acpi_pm_tmr_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
 {
     ar->tmr.update_sci = update_sci;
     ar->tmr.timer = qemu_new_timer_ns(vm_clock, acpi_pm_tmr_timer, ar);
-    memory_region_init_io(&ar->tmr.io, &acpi_pm_tmr_ops, ar, "acpi-tmr", 4);
+    memory_region_init_io(&ar->tmr.io, NULL, &acpi_pm_tmr_ops, ar, "acpi-tmr", 4);
     memory_region_add_subregion(parent, 8, &ar->tmr.io);
 }
 
@@ -552,7 +552,7 @@ void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, uint8_t s4_val)
     ar->pm1.cnt.s4_val = s4_val;
     ar->wakeup.notify = acpi_notify_wakeup;
     qemu_register_wakeup_notifier(&ar->wakeup);
-    memory_region_init_io(&ar->pm1.cnt.io, &acpi_pm_cnt_ops, ar, "acpi-cnt", 2);
+    memory_region_init_io(&ar->pm1.cnt.io, NULL, &acpi_pm_cnt_ops, ar, "acpi-cnt", 2);
     memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io);
 }
 
diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
index 4a17f32b96..8ce52e78c8 100644
--- a/hw/acpi/ich9.c
+++ b/hw/acpi/ich9.c
@@ -205,7 +205,7 @@ static void pm_powerdown_req(Notifier *n, void *opaque)
 void ich9_pm_init(PCIDevice *lpc_pci, ICH9LPCPMRegs *pm,
                   qemu_irq sci_irq)
 {
-    memory_region_init(&pm->io, "ich9-pm", ICH9_PMIO_SIZE);
+    memory_region_init(&pm->io, NULL, "ich9-pm", ICH9_PMIO_SIZE);
     memory_region_set_enabled(&pm->io, false);
     memory_region_add_subregion(pci_address_space_io(lpc_pci),
                                 0, &pm->io);
@@ -215,11 +215,11 @@ void ich9_pm_init(PCIDevice *lpc_pci, ICH9LPCPMRegs *pm,
     acpi_pm1_cnt_init(&pm->acpi_regs, &pm->io, 2);
 
     acpi_gpe_init(&pm->acpi_regs, ICH9_PMIO_GPE0_LEN);
-    memory_region_init_io(&pm->io_gpe, &ich9_gpe_ops, pm, "apci-gpe0",
+    memory_region_init_io(&pm->io_gpe, NULL, &ich9_gpe_ops, pm, "apci-gpe0",
                           ICH9_PMIO_GPE0_LEN);
     memory_region_add_subregion(&pm->io, ICH9_PMIO_GPE0_STS, &pm->io_gpe);
 
-    memory_region_init_io(&pm->io_smi, &ich9_smi_ops, pm, "apci-smi",
+    memory_region_init_io(&pm->io_smi, NULL, &ich9_smi_ops, pm, "apci-smi",
                           8);
     memory_region_add_subregion(&pm->io, ICH9_PMIO_SMI_EN, &pm->io_smi);
 
diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index ff559c0a4a..3b95c69ba4 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -424,7 +424,7 @@ static int piix4_pm_initfn(PCIDevice *dev)
     memory_region_add_subregion(pci_address_space_io(dev),
                                 s->smb_io_base, &s->smb.io);
 
-    memory_region_init(&s->io, "piix4-pm", 64);
+    memory_region_init(&s->io, NULL, "piix4-pm", 64);
     memory_region_set_enabled(&s->io, false);
     memory_region_add_subregion(pci_address_space_io(dev),
                                 0, &s->io);
@@ -671,18 +671,18 @@ static int piix4_device_hotplug(DeviceState *qdev, PCIDevice *dev,
 static void piix4_acpi_system_hot_add_init(MemoryRegion *parent,
                                            PCIBus *bus, PIIX4PMState *s)
 {
-    memory_region_init_io(&s->io_gpe, &piix4_gpe_ops, s, "apci-gpe0",
+    memory_region_init_io(&s->io_gpe, NULL, &piix4_gpe_ops, s, "apci-gpe0",
                           GPE_LEN);
     memory_region_add_subregion(parent, GPE_BASE, &s->io_gpe);
 
-    memory_region_init_io(&s->io_pci, &piix4_pci_ops, s, "apci-pci-hotplug",
+    memory_region_init_io(&s->io_pci, NULL, &piix4_pci_ops, s, "apci-pci-hotplug",
                           PCI_HOTPLUG_SIZE);
     memory_region_add_subregion(parent, PCI_HOTPLUG_ADDR,
                                 &s->io_pci);
     pci_bus_hotplug(bus, piix4_device_hotplug, &s->dev.qdev);
 
     qemu_for_each_cpu(piix4_init_cpu_status, &s->gpe_cpu);
-    memory_region_init_io(&s->io_cpu, &cpu_hotplug_ops, s, "apci-cpu-hotplug",
+    memory_region_init_io(&s->io_cpu, NULL, &cpu_hotplug_ops, s, "apci-cpu-hotplug",
                           PIIX4_PROC_LEN);
     memory_region_add_subregion(parent, PIIX4_PROC_BASE, &s->io_cpu);
     s->cpu_added_notifier.notify = piix4_cpu_added_req;
diff --git a/hw/alpha/typhoon.c b/hw/alpha/typhoon.c
index 207dcad2a3..99427e82d9 100644
--- a/hw/alpha/typhoon.c
+++ b/hw/alpha/typhoon.c
@@ -741,7 +741,7 @@ PCIBus *typhoon_init(ram_addr_t ram_size, ISABus **isa_bus,
 
     /* Main memory region, 0x00.0000.0000.  Real hardware supports 32GB,
        but the address space hole reserved at this point is 8TB.  */
-    memory_region_init_ram(&s->ram_region, "ram", ram_size);
+    memory_region_init_ram(&s->ram_region, NULL, "ram", ram_size);
     vmstate_register_ram_global(&s->ram_region);
     memory_region_add_subregion(addr_space, 0, &s->ram_region);
 
@@ -750,22 +750,22 @@ PCIBus *typhoon_init(ram_addr_t ram_size, ISABus **isa_bus,
        the flash ROM.  I'm not sure that we need to implement it at all.  */
 
     /* Pchip0 CSRs, 0x801.8000.0000, 256MB.  */
-    memory_region_init_io(&s->pchip.region, &pchip_ops, s, "pchip0", 256*MB);
+    memory_region_init_io(&s->pchip.region, NULL, &pchip_ops, s, "pchip0", 256*MB);
     memory_region_add_subregion(addr_space, 0x80180000000ULL,
                                 &s->pchip.region);
 
     /* Cchip CSRs, 0x801.A000.0000, 256MB.  */
-    memory_region_init_io(&s->cchip.region, &cchip_ops, s, "cchip0", 256*MB);
+    memory_region_init_io(&s->cchip.region, NULL, &cchip_ops, s, "cchip0", 256*MB);
     memory_region_add_subregion(addr_space, 0x801a0000000ULL,
                                 &s->cchip.region);
 
     /* Dchip CSRs, 0x801.B000.0000, 256MB.  */
-    memory_region_init_io(&s->dchip_region, &dchip_ops, s, "dchip0", 256*MB);
+    memory_region_init_io(&s->dchip_region, NULL, &dchip_ops, s, "dchip0", 256*MB);
     memory_region_add_subregion(addr_space, 0x801b0000000ULL,
                                 &s->dchip_region);
 
     /* Pchip0 PCI memory, 0x800.0000.0000, 4GB.  */
-    memory_region_init(&s->pchip.reg_mem, "pci0-mem", 4*GB);
+    memory_region_init(&s->pchip.reg_mem, NULL, "pci0-mem", 4*GB);
     memory_region_add_subregion(addr_space, 0x80000000000ULL,
                                 &s->pchip.reg_mem);
 
@@ -773,7 +773,7 @@ PCIBus *typhoon_init(ram_addr_t ram_size, ISABus **isa_bus,
     /* ??? Ideally we drop the "system" i/o space on the floor and give the
        PCI subsystem the full address space reserved by the chipset.
        We can't do that until the MEM and IO paths in memory.c are unified.  */
-    memory_region_init_io(&s->pchip.reg_io, &alpha_pci_bw_io_ops, NULL,
+    memory_region_init_io(&s->pchip.reg_io, NULL, &alpha_pci_bw_io_ops, NULL,
                           "pci0-io", 32*MB);
     memory_region_add_subregion(addr_space, 0x801fc000000ULL,
                                 &s->pchip.reg_io);
@@ -784,13 +784,13 @@ PCIBus *typhoon_init(ram_addr_t ram_size, ISABus **isa_bus,
     phb->bus = b;
 
     /* Pchip0 PCI special/interrupt acknowledge, 0x801.F800.0000, 64MB.  */
-    memory_region_init_io(&s->pchip.reg_iack, &alpha_pci_iack_ops, b,
+    memory_region_init_io(&s->pchip.reg_iack, NULL, &alpha_pci_iack_ops, b,
                           "pci0-iack", 64*MB);
     memory_region_add_subregion(addr_space, 0x801f8000000ULL,
                                 &s->pchip.reg_iack);
 
     /* Pchip0 PCI configuration, 0x801.FE00.0000, 16MB.  */
-    memory_region_init_io(&s->pchip.reg_conf, &alpha_pci_conf1_ops, b,
+    memory_region_init_io(&s->pchip.reg_conf, NULL, &alpha_pci_conf1_ops, b,
                           "pci0-conf", 16*MB);
     memory_region_add_subregion(addr_space, 0x801fe000000ULL,
                                 &s->pchip.reg_conf);
diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c
index 93422bc7be..4b82bbaf9e 100644
--- a/hw/arm/armv7m.c
+++ b/hw/arm/armv7m.c
@@ -124,7 +124,7 @@ static int bitband_init(SysBusDevice *dev)
 {
     BitBandState *s = FROM_SYSBUS(BitBandState, dev);
 
-    memory_region_init_io(&s->iomem, &bitband_ops, &s->base, "bitband",
+    memory_region_init_io(&s->iomem, NULL, &bitband_ops, &s->base, "bitband",
                           0x02000000);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
@@ -203,11 +203,11 @@ qemu_irq *armv7m_init(MemoryRegion *address_space_mem,
 #endif
 
     /* Flash programming is done via the SCU, so pretend it is ROM.  */
-    memory_region_init_ram(flash, "armv7m.flash", flash_size);
+    memory_region_init_ram(flash, NULL, "armv7m.flash", flash_size);
     vmstate_register_ram_global(flash);
     memory_region_set_readonly(flash, true);
     memory_region_add_subregion(address_space_mem, 0, flash);
-    memory_region_init_ram(sram, "armv7m.sram", sram_size);
+    memory_region_init_ram(sram, NULL, "armv7m.sram", sram_size);
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(address_space_mem, 0x20000000, sram);
     armv7m_bitband_init();
@@ -247,7 +247,7 @@ qemu_irq *armv7m_init(MemoryRegion *address_space_mem,
     /* Hack to map an additional page of ram at the top of the address
        space.  This stops qemu complaining about executing code outside RAM
        when returning from an exception.  */
-    memory_region_init_ram(hack, "armv7m.hack", 0x1000);
+    memory_region_init_ram(hack, NULL, "armv7m.hack", 0x1000);
     vmstate_register_ram_global(hack);
     memory_region_add_subregion(address_space_mem, 0xfffff000, hack);
 
diff --git a/hw/arm/exynos4210.c b/hw/arm/exynos4210.c
index 8186f1486b..216b9b77d9 100644
--- a/hw/arm/exynos4210.c
+++ b/hw/arm/exynos4210.c
@@ -241,20 +241,20 @@ Exynos4210State *exynos4210_init(MemoryRegion *system_mem,
     /*** Memory ***/
 
     /* Chip-ID and OMR */
-    memory_region_init_io(&s->chipid_mem, &exynos4210_chipid_and_omr_ops,
+    memory_region_init_io(&s->chipid_mem, NULL, &exynos4210_chipid_and_omr_ops,
         NULL, "exynos4210.chipid", sizeof(chipid_and_omr));
     memory_region_add_subregion(system_mem, EXYNOS4210_CHIPID_ADDR,
                                 &s->chipid_mem);
 
     /* Internal ROM */
-    memory_region_init_ram(&s->irom_mem, "exynos4210.irom",
+    memory_region_init_ram(&s->irom_mem, NULL, "exynos4210.irom",
                            EXYNOS4210_IROM_SIZE);
     vmstate_register_ram_global(&s->irom_mem);
     memory_region_set_readonly(&s->irom_mem, true);
     memory_region_add_subregion(system_mem, EXYNOS4210_IROM_BASE_ADDR,
                                 &s->irom_mem);
     /* mirror of iROM */
-    memory_region_init_alias(&s->irom_alias_mem, "exynos4210.irom_alias",
+    memory_region_init_alias(&s->irom_alias_mem, NULL, "exynos4210.irom_alias",
                              &s->irom_mem,
                              0,
                              EXYNOS4210_IROM_SIZE);
@@ -263,7 +263,7 @@ Exynos4210State *exynos4210_init(MemoryRegion *system_mem,
                                 &s->irom_alias_mem);
 
     /* Internal RAM */
-    memory_region_init_ram(&s->iram_mem, "exynos4210.iram",
+    memory_region_init_ram(&s->iram_mem, NULL, "exynos4210.iram",
                            EXYNOS4210_IRAM_SIZE);
     vmstate_register_ram_global(&s->iram_mem);
     memory_region_add_subregion(system_mem, EXYNOS4210_IRAM_BASE_ADDR,
@@ -272,14 +272,14 @@ Exynos4210State *exynos4210_init(MemoryRegion *system_mem,
     /* DRAM */
     mem_size = ram_size;
     if (mem_size > EXYNOS4210_DRAM_MAX_SIZE) {
-        memory_region_init_ram(&s->dram1_mem, "exynos4210.dram1",
+        memory_region_init_ram(&s->dram1_mem, NULL, "exynos4210.dram1",
                 mem_size - EXYNOS4210_DRAM_MAX_SIZE);
         vmstate_register_ram_global(&s->dram1_mem);
         memory_region_add_subregion(system_mem, EXYNOS4210_DRAM1_BASE_ADDR,
                 &s->dram1_mem);
         mem_size = EXYNOS4210_DRAM_MAX_SIZE;
     }
-    memory_region_init_ram(&s->dram0_mem, "exynos4210.dram0", mem_size);
+    memory_region_init_ram(&s->dram0_mem, NULL, "exynos4210.dram0", mem_size);
     vmstate_register_ram_global(&s->dram0_mem);
     memory_region_add_subregion(system_mem, EXYNOS4210_DRAM0_BASE_ADDR,
             &s->dram0_mem);
diff --git a/hw/arm/highbank.c b/hw/arm/highbank.c
index 4405dbd3bd..c02afceb5f 100644
--- a/hw/arm/highbank.c
+++ b/hw/arm/highbank.c
@@ -149,7 +149,7 @@ static int highbank_regs_init(SysBusDevice *dev)
     HighbankRegsState *s = FROM_SYSBUS(HighbankRegsState, dev);
 
     s->iomem = g_new(MemoryRegion, 1);
-    memory_region_init_io(s->iomem, &hb_mem_ops, s->regs, "highbank_regs",
+    memory_region_init_io(s->iomem, NULL, &hb_mem_ops, s->regs, "highbank_regs",
                           0x1000);
     sysbus_init_mmio(dev, s->iomem);
 
@@ -227,12 +227,12 @@ static void highbank_init(QEMUMachineInitArgs *args)
 
     sysmem = get_system_memory();
     dram = g_new(MemoryRegion, 1);
-    memory_region_init_ram(dram, "highbank.dram", ram_size);
+    memory_region_init_ram(dram, NULL, "highbank.dram", ram_size);
     /* SDRAM at address zero.  */
     memory_region_add_subregion(sysmem, 0, dram);
 
     sysram = g_new(MemoryRegion, 1);
-    memory_region_init_ram(sysram, "highbank.sysram", 0x8000);
+    memory_region_init_ram(sysram, NULL, "highbank.sysram", 0x8000);
     memory_region_add_subregion(sysmem, 0xfff88000, sysram);
     if (bios_name != NULL) {
         sysboot_filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
diff --git a/hw/arm/integratorcp.c b/hw/arm/integratorcp.c
index cca29719ec..436d89b303 100644
--- a/hw/arm/integratorcp.c
+++ b/hw/arm/integratorcp.c
@@ -249,10 +249,10 @@ static int integratorcm_init(SysBusDevice *dev)
     }
     memcpy(integrator_spd + 73, "QEMU-MEMORY", 11);
     s->cm_init = 0x00000112;
-    memory_region_init_ram(&s->flash, "integrator.flash", 0x100000);
+    memory_region_init_ram(&s->flash, NULL, "integrator.flash", 0x100000);
     vmstate_register_ram_global(&s->flash);
 
-    memory_region_init_io(&s->iomem, &integratorcm_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &integratorcm_ops, s,
                           "integratorcm", 0x00800000);
     sysbus_init_mmio(dev, &s->iomem);
 
@@ -374,7 +374,7 @@ static int icp_pic_init(SysBusDevice *dev)
     qdev_init_gpio_in(&dev->qdev, icp_pic_set_irq, 32);
     sysbus_init_irq(dev, &s->parent_irq);
     sysbus_init_irq(dev, &s->parent_fiq);
-    memory_region_init_io(&s->iomem, &icp_pic_ops, s, "icp-pic", 0x00800000);
+    memory_region_init_io(&s->iomem, NULL, &icp_pic_ops, s, "icp-pic", 0x00800000);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
 }
@@ -424,7 +424,7 @@ static void icp_control_init(hwaddr base)
     MemoryRegion *io;
 
     io = (MemoryRegion *)g_malloc0(sizeof(MemoryRegion));
-    memory_region_init_io(io, &icp_control_ops, NULL,
+    memory_region_init_io(io, NULL, &icp_control_ops, NULL,
                           "control", 0x00800000);
     memory_region_add_subregion(get_system_memory(), base, io);
     /* ??? Save/restore.  */
@@ -463,14 +463,14 @@ static void integratorcp_init(QEMUMachineInitArgs *args)
         exit(1);
     }
 
-    memory_region_init_ram(ram, "integrator.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "integrator.ram", ram_size);
     vmstate_register_ram_global(ram);
     /* ??? On a real system the first 1Mb is mapped as SSRAM or boot flash.  */
     /* ??? RAM should repeat to fill physical memory space.  */
     /* SDRAM at address zero*/
     memory_region_add_subregion(address_space_mem, 0, ram);
     /* And again at address 0x80000000 */
-    memory_region_init_alias(ram_alias, "ram.alias", ram, 0, ram_size);
+    memory_region_init_alias(ram_alias, NULL, "ram.alias", ram, 0, ram_size);
     memory_region_add_subregion(address_space_mem, 0x80000000, ram_alias);
 
     dev = qdev_create(NULL, "integrator_core");
diff --git a/hw/arm/kzm.c b/hw/arm/kzm.c
index cf90f5dc71..bd6c05ce1b 100644
--- a/hw/arm/kzm.c
+++ b/hw/arm/kzm.c
@@ -98,14 +98,14 @@ static void kzm_init(QEMUMachineInitArgs *args)
 
     /* On a real system, the first 16k is a `secure boot rom' */
 
-    memory_region_init_ram(ram, "kzm.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "kzm.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, KZM_RAMADDRESS, ram);
 
-    memory_region_init_alias(ram_alias, "ram.alias", ram, 0, ram_size);
+    memory_region_init_alias(ram_alias, NULL, "ram.alias", ram, 0, ram_size);
     memory_region_add_subregion(address_space_mem, 0x88000000, ram_alias);
 
-    memory_region_init_ram(sram, "kzm.sram", 0x4000);
+    memory_region_init_ram(sram, NULL, "kzm.sram", 0x4000);
     memory_region_add_subregion(address_space_mem, 0x1FFFC000, sram);
 
     cpu_pic = arm_pic_init_cpu(cpu);
diff --git a/hw/arm/mainstone.c b/hw/arm/mainstone.c
index 260e31481d..8e5fc26e12 100644
--- a/hw/arm/mainstone.c
+++ b/hw/arm/mainstone.c
@@ -113,7 +113,7 @@ static void mainstone_common_init(MemoryRegion *address_space_mem,
 
     /* Setup CPU & memory */
     mpu = pxa270_init(address_space_mem, mainstone_binfo.ram_size, cpu_model);
-    memory_region_init_ram(rom, "mainstone.rom", MAINSTONE_ROM);
+    memory_region_init_ram(rom, NULL, "mainstone.rom", MAINSTONE_ROM);
     vmstate_register_ram_global(rom);
     memory_region_set_readonly(rom, true);
     memory_region_add_subregion(address_space_mem, 0, rom);
diff --git a/hw/arm/musicpal.c b/hw/arm/musicpal.c
index fbaf2be701..bca8fdf060 100644
--- a/hw/arm/musicpal.c
+++ b/hw/arm/musicpal.c
@@ -389,7 +389,7 @@ static int mv88w8618_eth_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq);
     s->nic = qemu_new_nic(&net_mv88w8618_info, &s->conf,
                           object_get_typename(OBJECT(dev)), dev->qdev.id, s);
-    memory_region_init_io(&s->iomem, &mv88w8618_eth_ops, s, "mv88w8618-eth",
+    memory_region_init_io(&s->iomem, NULL, &mv88w8618_eth_ops, s, "mv88w8618-eth",
                           MP_ETH_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
@@ -612,7 +612,7 @@ static int musicpal_lcd_init(SysBusDevice *dev)
 
     s->brightness = 7;
 
-    memory_region_init_io(&s->iomem, &musicpal_lcd_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &musicpal_lcd_ops, s,
                           "musicpal-lcd", MP_LCD_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
@@ -740,7 +740,7 @@ static int mv88w8618_pic_init(SysBusDevice *dev)
 
     qdev_init_gpio_in(&dev->qdev, mv88w8618_pic_set_irq, 32);
     sysbus_init_irq(dev, &s->parent_irq);
-    memory_region_init_io(&s->iomem, &mv88w8618_pic_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &mv88w8618_pic_ops, s,
                           "musicpal-pic", MP_PIC_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
@@ -905,7 +905,7 @@ static int mv88w8618_pit_init(SysBusDevice *dev)
         mv88w8618_timer_init(dev, &s->timer[i], 1000000);
     }
 
-    memory_region_init_io(&s->iomem, &mv88w8618_pit_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &mv88w8618_pit_ops, s,
                           "musicpal-pit", MP_PIT_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
@@ -999,7 +999,7 @@ static int mv88w8618_flashcfg_init(SysBusDevice *dev)
     mv88w8618_flashcfg_state *s = FROM_SYSBUS(mv88w8618_flashcfg_state, dev);
 
     s->cfgr0 = 0xfffe4285; /* Default as set by U-Boot for 8 MB flash */
-    memory_region_init_io(&s->iomem, &mv88w8618_flashcfg_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &mv88w8618_flashcfg_ops, s,
                           "musicpal-flashcfg", MP_FLASHCFG_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
@@ -1074,7 +1074,7 @@ static void musicpal_misc_init(Object *obj)
     SysBusDevice *sd = SYS_BUS_DEVICE(obj);
     MusicPalMiscState *s = MUSICPAL_MISC(obj);
 
-    memory_region_init_io(&s->iomem, &musicpal_misc_ops, NULL,
+    memory_region_init_io(&s->iomem, NULL, &musicpal_misc_ops, NULL,
                           "musicpal-misc", MP_MISC_SIZE);
     sysbus_init_mmio(sd, &s->iomem);
 }
@@ -1121,7 +1121,7 @@ static int mv88w8618_wlan_init(SysBusDevice *dev)
 {
     MemoryRegion *iomem = g_new(MemoryRegion, 1);
 
-    memory_region_init_io(iomem, &mv88w8618_wlan_ops, NULL,
+    memory_region_init_io(iomem, NULL, &mv88w8618_wlan_ops, NULL,
                           "musicpal-wlan", MP_WLAN_SIZE);
     sysbus_init_mmio(dev, iomem);
     return 0;
@@ -1327,7 +1327,7 @@ static int musicpal_gpio_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->iomem, &musicpal_gpio_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &musicpal_gpio_ops, s,
                           "musicpal-gpio", MP_GPIO_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
@@ -1484,7 +1484,7 @@ static int musicpal_key_init(SysBusDevice *dev)
 {
     musicpal_key_state *s = FROM_SYSBUS(musicpal_key_state, dev);
 
-    memory_region_init(&s->iomem, "dummy", 0);
+    memory_region_init(&s->iomem, NULL, "dummy", 0);
     sysbus_init_mmio(dev, &s->iomem);
 
     s->kbd_extended = 0;
@@ -1564,11 +1564,11 @@ static void musicpal_init(QEMUMachineInitArgs *args)
     cpu_pic = arm_pic_init_cpu(cpu);
 
     /* For now we use a fixed - the original - RAM size */
-    memory_region_init_ram(ram, "musicpal.ram", MP_RAM_DEFAULT_SIZE);
+    memory_region_init_ram(ram, NULL, "musicpal.ram", MP_RAM_DEFAULT_SIZE);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, 0, ram);
 
-    memory_region_init_ram(sram, "musicpal.sram", MP_SRAM_SIZE);
+    memory_region_init_ram(sram, NULL, "musicpal.sram", MP_SRAM_SIZE);
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(address_space_mem, MP_SRAM_BASE, sram);
 
diff --git a/hw/arm/omap1.c b/hw/arm/omap1.c
index c06c642acc..19be5fcd01 100644
--- a/hw/arm/omap1.c
+++ b/hw/arm/omap1.c
@@ -264,7 +264,7 @@ static struct omap_mpu_timer_s *omap_mpu_timer_init(MemoryRegion *system_memory,
     omap_mpu_timer_reset(s);
     omap_timer_clk_setup(s);
 
-    memory_region_init_io(&s->iomem, &omap_mpu_timer_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_mpu_timer_ops, s,
                           "omap-mpu-timer", 0x100);
 
     memory_region_add_subregion(system_memory, base, &s->iomem);
@@ -392,7 +392,7 @@ static struct omap_watchdog_timer_s *omap_wd_timer_init(MemoryRegion *memory,
     omap_wd_timer_reset(s);
     omap_timer_clk_setup(&s->timer);
 
-    memory_region_init_io(&s->iomem, &omap_wd_timer_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_wd_timer_ops, s,
                           "omap-wd-timer", 0x100);
     memory_region_add_subregion(memory, base, &s->iomem);
 
@@ -498,7 +498,7 @@ static struct omap_32khz_timer_s *omap_os_timer_init(MemoryRegion *memory,
     omap_os_timer_reset(s);
     omap_timer_clk_setup(&s->timer);
 
-    memory_region_init_io(&s->iomem, &omap_os_timer_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_os_timer_ops, s,
                           "omap-os-timer", 0x800);
     memory_region_add_subregion(memory, base, &s->iomem);
 
@@ -731,7 +731,7 @@ static void omap_ulpd_pm_init(MemoryRegion *system_memory,
                 hwaddr base,
                 struct omap_mpu_state_s *mpu)
 {
-    memory_region_init_io(&mpu->ulpd_pm_iomem, &omap_ulpd_pm_ops, mpu,
+    memory_region_init_io(&mpu->ulpd_pm_iomem, NULL, &omap_ulpd_pm_ops, mpu,
                           "omap-ulpd-pm", 0x800);
     memory_region_add_subregion(system_memory, base, &mpu->ulpd_pm_iomem);
     omap_ulpd_pm_reset(mpu);
@@ -949,7 +949,7 @@ static void omap_pin_cfg_init(MemoryRegion *system_memory,
                 hwaddr base,
                 struct omap_mpu_state_s *mpu)
 {
-    memory_region_init_io(&mpu->pin_cfg_iomem, &omap_pin_cfg_ops, mpu,
+    memory_region_init_io(&mpu->pin_cfg_iomem, NULL, &omap_pin_cfg_ops, mpu,
                           "omap-pin-cfg", 0x800);
     memory_region_add_subregion(system_memory, base, &mpu->pin_cfg_iomem);
     omap_pin_cfg_reset(mpu);
@@ -1021,16 +1021,16 @@ static const MemoryRegionOps omap_id_ops = {
 
 static void omap_id_init(MemoryRegion *memory, struct omap_mpu_state_s *mpu)
 {
-    memory_region_init_io(&mpu->id_iomem, &omap_id_ops, mpu,
+    memory_region_init_io(&mpu->id_iomem, NULL, &omap_id_ops, mpu,
                           "omap-id", 0x100000000ULL);
-    memory_region_init_alias(&mpu->id_iomem_e18, "omap-id-e18", &mpu->id_iomem,
+    memory_region_init_alias(&mpu->id_iomem_e18, NULL, "omap-id-e18", &mpu->id_iomem,
                              0xfffe1800, 0x800);
     memory_region_add_subregion(memory, 0xfffe1800, &mpu->id_iomem_e18);
-    memory_region_init_alias(&mpu->id_iomem_ed4, "omap-id-ed4", &mpu->id_iomem,
+    memory_region_init_alias(&mpu->id_iomem_ed4, NULL, "omap-id-ed4", &mpu->id_iomem,
                              0xfffed400, 0x100);
     memory_region_add_subregion(memory, 0xfffed400, &mpu->id_iomem_ed4);
     if (!cpu_is_omap15xx(mpu)) {
-        memory_region_init_alias(&mpu->id_iomem_ed4, "omap-id-e20",
+        memory_region_init_alias(&mpu->id_iomem_ed4, NULL, "omap-id-e20",
                                  &mpu->id_iomem, 0xfffe2000, 0x800);
         memory_region_add_subregion(memory, 0xfffe2000, &mpu->id_iomem_e20);
     }
@@ -1115,7 +1115,7 @@ static void omap_mpui_reset(struct omap_mpu_state_s *s)
 static void omap_mpui_init(MemoryRegion *memory, hwaddr base,
                 struct omap_mpu_state_s *mpu)
 {
-    memory_region_init_io(&mpu->mpui_iomem, &omap_mpui_ops, mpu,
+    memory_region_init_io(&mpu->mpui_iomem, NULL, &omap_mpui_ops, mpu,
                           "omap-mpui", 0x100);
     memory_region_add_subregion(memory, base, &mpu->mpui_iomem);
 
@@ -1227,7 +1227,7 @@ static struct omap_tipb_bridge_s *omap_tipb_bridge_init(
     s->abort = abort_irq;
     omap_tipb_bridge_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_tipb_bridge_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_tipb_bridge_ops, s,
                           "omap-tipb-bridge", 0x100);
     memory_region_add_subregion(memory, base, &s->iomem);
 
@@ -1336,7 +1336,7 @@ static void omap_tcmi_reset(struct omap_mpu_state_s *mpu)
 static void omap_tcmi_init(MemoryRegion *memory, hwaddr base,
                 struct omap_mpu_state_s *mpu)
 {
-    memory_region_init_io(&mpu->tcmi_iomem, &omap_tcmi_ops, mpu,
+    memory_region_init_io(&mpu->tcmi_iomem, NULL, &omap_tcmi_ops, mpu,
                           "omap-tcmi", 0x100);
     memory_region_add_subregion(memory, base, &mpu->tcmi_iomem);
     omap_tcmi_reset(mpu);
@@ -1418,7 +1418,7 @@ static struct dpll_ctl_s  *omap_dpll_init(MemoryRegion *memory,
                            hwaddr base, omap_clk clk)
 {
     struct dpll_ctl_s *s = g_malloc0(sizeof(*s));
-    memory_region_init_io(&s->iomem, &omap_dpll_ops, s, "omap-dpll", 0x100);
+    memory_region_init_io(&s->iomem, NULL, &omap_dpll_ops, s, "omap-dpll", 0x100);
 
     s->dpll = clk;
     omap_dpll_reset(s);
@@ -1831,9 +1831,9 @@ static void omap_clkm_reset(struct omap_mpu_state_s *s)
 static void omap_clkm_init(MemoryRegion *memory, hwaddr mpu_base,
                 hwaddr dsp_base, struct omap_mpu_state_s *s)
 {
-    memory_region_init_io(&s->clkm_iomem, &omap_clkm_ops, s,
+    memory_region_init_io(&s->clkm_iomem, NULL, &omap_clkm_ops, s,
                           "omap-clkm", 0x100);
-    memory_region_init_io(&s->clkdsp_iomem, &omap_clkdsp_ops, s,
+    memory_region_init_io(&s->clkdsp_iomem, NULL, &omap_clkdsp_ops, s,
                           "omap-clkdsp", 0x1000);
 
     s->clkm.arm_idlect1 = 0x03ff;
@@ -2090,7 +2090,7 @@ static struct omap_mpuio_s *omap_mpuio_init(MemoryRegion *memory,
     s->in = qemu_allocate_irqs(omap_mpuio_set, s, 16);
     omap_mpuio_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_mpuio_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_mpuio_ops, s,
                           "omap-mpuio", 0x800);
     memory_region_add_subregion(memory, base, &s->iomem);
 
@@ -2281,7 +2281,7 @@ static struct omap_uwire_s *omap_uwire_init(MemoryRegion *system_memory,
     s->txdrq = dma;
     omap_uwire_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_uwire_ops, s, "omap-uwire", 0x800);
+    memory_region_init_io(&s->iomem, NULL, &omap_uwire_ops, s, "omap-uwire", 0x800);
     memory_region_add_subregion(system_memory, base, &s->iomem);
 
     return s;
@@ -2393,7 +2393,7 @@ static struct omap_pwl_s *omap_pwl_init(MemoryRegion *system_memory,
 
     omap_pwl_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_pwl_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_pwl_ops, s,
                           "omap-pwl", 0x800);
     memory_region_add_subregion(system_memory, base, &s->iomem);
 
@@ -2500,7 +2500,7 @@ static struct omap_pwt_s *omap_pwt_init(MemoryRegion *system_memory,
     s->clk = clk;
     omap_pwt_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_pwt_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_pwt_ops, s,
                           "omap-pwt", 0x800);
     memory_region_add_subregion(system_memory, base, &s->iomem);
     return s;
@@ -2919,7 +2919,7 @@ static struct omap_rtc_s *omap_rtc_init(MemoryRegion *system_memory,
 
     omap_rtc_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_rtc_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &omap_rtc_ops, s,
                           "omap-rtc", 0x800);
     memory_region_add_subregion(system_memory, base, &s->iomem);
 
@@ -3452,7 +3452,7 @@ static struct omap_mcbsp_s *omap_mcbsp_init(MemoryRegion *system_memory,
     s->source_timer = qemu_new_timer_ns(vm_clock, omap_mcbsp_source_tick, s);
     omap_mcbsp_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_mcbsp_ops, s, "omap-mcbsp", 0x800);
+    memory_region_init_io(&s->iomem, NULL, &omap_mcbsp_ops, s, "omap-mcbsp", 0x800);
     memory_region_add_subregion(system_memory, base, &s->iomem);
 
     return s;
@@ -3627,7 +3627,7 @@ static struct omap_lpg_s *omap_lpg_init(MemoryRegion *system_memory,
 
     omap_lpg_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_lpg_ops, s, "omap-lpg", 0x800);
+    memory_region_init_io(&s->iomem, NULL, &omap_lpg_ops, s, "omap-lpg", 0x800);
     memory_region_add_subregion(system_memory, base, &s->iomem);
 
     omap_clk_adduser(clk, qemu_allocate_irqs(omap_lpg_clk_update, s, 1)[0]);
@@ -3666,7 +3666,7 @@ static const MemoryRegionOps omap_mpui_io_ops = {
 static void omap_setup_mpui_io(MemoryRegion *system_memory,
                                struct omap_mpu_state_s *mpu)
 {
-    memory_region_init_io(&mpu->mpui_io_iomem, &omap_mpui_io_ops, mpu,
+    memory_region_init_io(&mpu->mpui_io_iomem, NULL, &omap_mpui_io_ops, mpu,
                           "omap-mpui-io", 0x7fff);
     memory_region_add_subregion(system_memory, OMAP_MPUI_BASE,
                                 &mpu->mpui_io_iomem);
@@ -3747,7 +3747,7 @@ static void omap_setup_dsp_mapping(MemoryRegion *system_memory,
 
     for (; map->phys_dsp; map ++) {
         io = g_new(MemoryRegion, 1);
-        memory_region_init_alias(io, map->name,
+        memory_region_init_alias(io, NULL, map->name,
                                  system_memory, map->phys_mpu, map->size);
         memory_region_add_subregion(system_memory, map->phys_dsp, io);
     }
@@ -3851,10 +3851,10 @@ struct omap_mpu_state_s *omap310_mpu_init(MemoryRegion *system_memory,
     omap_clk_init(s);
 
     /* Memory-mapped stuff */
-    memory_region_init_ram(&s->emiff_ram, "omap1.dram", s->sdram_size);
+    memory_region_init_ram(&s->emiff_ram, NULL, "omap1.dram", s->sdram_size);
     vmstate_register_ram_global(&s->emiff_ram);
     memory_region_add_subregion(system_memory, OMAP_EMIFF_BASE, &s->emiff_ram);
-    memory_region_init_ram(&s->imif_ram, "omap1.sram", s->sram_size);
+    memory_region_init_ram(&s->imif_ram, NULL, "omap1.sram", s->sram_size);
     vmstate_register_ram_global(&s->imif_ram);
     memory_region_add_subregion(system_memory, OMAP_IMIF_BASE, &s->imif_ram);
 
diff --git a/hw/arm/omap2.c b/hw/arm/omap2.c
index 2ff43710e4..ec9610b7d5 100644
--- a/hw/arm/omap2.c
+++ b/hw/arm/omap2.c
@@ -603,7 +603,7 @@ static struct omap_eac_s *omap_eac_init(struct omap_target_agent_s *ta,
 
     AUD_register_card("OMAP EAC", &s->codec.card);
 
-    memory_region_init_io(&s->iomem, &omap_eac_ops, s, "omap.eac",
+    memory_region_init_io(&s->iomem, NULL, &omap_eac_ops, s, "omap.eac",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &s->iomem);
 
@@ -791,11 +791,11 @@ static struct omap_sti_s *omap_sti_init(struct omap_target_agent_s *ta,
 
     s->chr = chr ?: qemu_chr_new("null", "null", NULL);
 
-    memory_region_init_io(&s->iomem, &omap_sti_ops, s, "omap.sti",
+    memory_region_init_io(&s->iomem, NULL, &omap_sti_ops, s, "omap.sti",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &s->iomem);
 
-    memory_region_init_io(&s->iomem_fifo, &omap_sti_fifo_ops, s,
+    memory_region_init_io(&s->iomem_fifo, NULL, &omap_sti_fifo_ops, s,
                           "omap.sti.fifo", 0x10000);
     memory_region_add_subregion(sysmem, channel_base, &s->iomem_fifo);
 
@@ -1809,9 +1809,9 @@ static struct omap_prcm_s *omap_prcm_init(struct omap_target_agent_s *ta,
     s->mpu = mpu;
     omap_prcm_coldreset(s);
 
-    memory_region_init_io(&s->iomem0, &omap_prcm_ops, s, "omap.pcrm0",
+    memory_region_init_io(&s->iomem0, NULL, &omap_prcm_ops, s, "omap.pcrm0",
                           omap_l4_region_size(ta, 0));
-    memory_region_init_io(&s->iomem1, &omap_prcm_ops, s, "omap.pcrm1",
+    memory_region_init_io(&s->iomem1, NULL, &omap_prcm_ops, s, "omap.pcrm1",
                           omap_l4_region_size(ta, 1));
     omap_l4_attach(ta, 0, &s->iomem0);
     omap_l4_attach(ta, 1, &s->iomem1);
@@ -2185,7 +2185,7 @@ static struct omap_sysctl_s *omap_sysctl_init(struct omap_target_agent_s *ta,
     s->mpu = mpu;
     omap_sysctl_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_sysctl_ops, s, "omap.sysctl",
+    memory_region_init_io(&s->iomem, NULL, &omap_sysctl_ops, s, "omap.sysctl",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &s->iomem);
 
@@ -2267,10 +2267,10 @@ struct omap_mpu_state_s *omap2420_mpu_init(MemoryRegion *sysmem,
     omap_clk_init(s);
 
     /* Memory-mapped stuff */
-    memory_region_init_ram(&s->sdram, "omap2.dram", s->sdram_size);
+    memory_region_init_ram(&s->sdram, NULL, "omap2.dram", s->sdram_size);
     vmstate_register_ram_global(&s->sdram);
     memory_region_add_subregion(sysmem, OMAP2_Q2_BASE, &s->sdram);
-    memory_region_init_ram(&s->sram, "omap2.sram", s->sram_size);
+    memory_region_init_ram(&s->sram, NULL, "omap2.sram", s->sram_size);
     vmstate_register_ram_global(&s->sram);
     memory_region_add_subregion(sysmem, OMAP2_SRAM_BASE, &s->sram);
 
diff --git a/hw/arm/omap_sx1.c b/hw/arm/omap_sx1.c
index e421ece026..05b035308b 100644
--- a/hw/arm/omap_sx1.c
+++ b/hw/arm/omap_sx1.c
@@ -120,23 +120,23 @@ static void sx1_init(QEMUMachineInitArgs *args, const int version)
     mpu = omap310_mpu_init(address_space, sx1_binfo.ram_size, args->cpu_model);
 
     /* External Flash (EMIFS) */
-    memory_region_init_ram(flash, "omap_sx1.flash0-0", flash_size);
+    memory_region_init_ram(flash, NULL, "omap_sx1.flash0-0", flash_size);
     vmstate_register_ram_global(flash);
     memory_region_set_readonly(flash, true);
     memory_region_add_subregion(address_space, OMAP_CS0_BASE, flash);
 
-    memory_region_init_io(&cs[0], &static_ops, &cs0val,
+    memory_region_init_io(&cs[0], NULL, &static_ops, &cs0val,
                           "sx1.cs0", OMAP_CS0_SIZE - flash_size);
     memory_region_add_subregion(address_space,
                                 OMAP_CS0_BASE + flash_size, &cs[0]);
 
 
-    memory_region_init_io(&cs[2], &static_ops, &cs2val,
+    memory_region_init_io(&cs[2], NULL, &static_ops, &cs2val,
                           "sx1.cs2", OMAP_CS2_SIZE);
     memory_region_add_subregion(address_space,
                                 OMAP_CS2_BASE, &cs[2]);
 
-    memory_region_init_io(&cs[3], &static_ops, &cs3val,
+    memory_region_init_io(&cs[3], NULL, &static_ops, &cs3val,
                           "sx1.cs3", OMAP_CS3_SIZE);
     memory_region_add_subregion(address_space,
                                 OMAP_CS2_BASE, &cs[3]);
@@ -162,12 +162,12 @@ static void sx1_init(QEMUMachineInitArgs *args, const int version)
 
     if ((version == 1) &&
             (dinfo = drive_get(IF_PFLASH, 0, fl_idx)) != NULL) {
-        memory_region_init_ram(flash_1, "omap_sx1.flash1-0", flash1_size);
+        memory_region_init_ram(flash_1, NULL, "omap_sx1.flash1-0", flash1_size);
         vmstate_register_ram_global(flash_1);
         memory_region_set_readonly(flash_1, true);
         memory_region_add_subregion(address_space, OMAP_CS1_BASE, flash_1);
 
-        memory_region_init_io(&cs[1], &static_ops, &cs1val,
+        memory_region_init_io(&cs[1], NULL, &static_ops, &cs1val,
                               "sx1.cs1", OMAP_CS1_SIZE - flash1_size);
         memory_region_add_subregion(address_space,
                                 OMAP_CS1_BASE + flash1_size, &cs[1]);
@@ -182,7 +182,7 @@ static void sx1_init(QEMUMachineInitArgs *args, const int version)
         }
         fl_idx++;
     } else {
-        memory_region_init_io(&cs[1], &static_ops, &cs1val,
+        memory_region_init_io(&cs[1], NULL, &static_ops, &cs1val,
                               "sx1.cs1", OMAP_CS1_SIZE);
         memory_region_add_subregion(address_space,
                                 OMAP_CS1_BASE, &cs[1]);
diff --git a/hw/arm/palm.c b/hw/arm/palm.c
index b13d8108a4..cdc3c3a0fe 100644
--- a/hw/arm/palm.c
+++ b/hw/arm/palm.c
@@ -211,22 +211,22 @@ static void palmte_init(QEMUMachineInitArgs *args)
     mpu = omap310_mpu_init(address_space_mem, sdram_size, cpu_model);
 
     /* External Flash (EMIFS) */
-    memory_region_init_ram(flash, "palmte.flash", flash_size);
+    memory_region_init_ram(flash, NULL, "palmte.flash", flash_size);
     vmstate_register_ram_global(flash);
     memory_region_set_readonly(flash, true);
     memory_region_add_subregion(address_space_mem, OMAP_CS0_BASE, flash);
 
-    memory_region_init_io(&cs[0], &static_ops, &cs0val, "palmte-cs0",
+    memory_region_init_io(&cs[0], NULL, &static_ops, &cs0val, "palmte-cs0",
                           OMAP_CS0_SIZE - flash_size);
     memory_region_add_subregion(address_space_mem, OMAP_CS0_BASE + flash_size,
                                 &cs[0]);
-    memory_region_init_io(&cs[1], &static_ops, &cs1val, "palmte-cs1",
+    memory_region_init_io(&cs[1], NULL, &static_ops, &cs1val, "palmte-cs1",
                           OMAP_CS1_SIZE);
     memory_region_add_subregion(address_space_mem, OMAP_CS1_BASE, &cs[1]);
-    memory_region_init_io(&cs[2], &static_ops, &cs2val, "palmte-cs2",
+    memory_region_init_io(&cs[2], NULL, &static_ops, &cs2val, "palmte-cs2",
                           OMAP_CS2_SIZE);
     memory_region_add_subregion(address_space_mem, OMAP_CS2_BASE, &cs[2]);
-    memory_region_init_io(&cs[3], &static_ops, &cs3val, "palmte-cs3",
+    memory_region_init_io(&cs[3], NULL, &static_ops, &cs3val, "palmte-cs3",
                           OMAP_CS3_SIZE);
     memory_region_add_subregion(address_space_mem, OMAP_CS3_BASE, &cs[3]);
 
diff --git a/hw/arm/pxa2xx.c b/hw/arm/pxa2xx.c
index 24b03a0d29..d046edc162 100644
--- a/hw/arm/pxa2xx.c
+++ b/hw/arm/pxa2xx.c
@@ -764,7 +764,7 @@ static int pxa2xx_ssp_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->iomem, &pxa2xx_ssp_ops, s, "pxa2xx-ssp", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_ssp_ops, s, "pxa2xx-ssp", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     register_savevm(&dev->qdev, "pxa2xx_ssp", -1, 0,
                     pxa2xx_ssp_save, pxa2xx_ssp_load, s);
@@ -1131,7 +1131,7 @@ static int pxa2xx_rtc_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->rtc_irq);
 
-    memory_region_init_io(&s->iomem, &pxa2xx_rtc_ops, s, "pxa2xx-rtc", 0x10000);
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_rtc_ops, s, "pxa2xx-rtc", 0x10000);
     sysbus_init_mmio(dev, &s->iomem);
 
     return 0;
@@ -1481,7 +1481,7 @@ static int pxa2xx_i2c_initfn(SysBusDevice *dev)
 
     s->bus = i2c_init_bus(&dev->qdev, "i2c");
 
-    memory_region_init_io(&s->iomem, &pxa2xx_i2c_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_i2c_ops, s,
                           "pxa2xx-i2x", s->region_size);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
@@ -1720,7 +1720,7 @@ static PXA2xxI2SState *pxa2xx_i2s_init(MemoryRegion *sysmem,
 
     pxa2xx_i2s_reset(s);
 
-    memory_region_init_io(&s->iomem, &pxa2xx_i2s_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_i2s_ops, s,
                           "pxa2xx-i2s", 0x100000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
@@ -1978,7 +1978,7 @@ static PXA2xxFIrState *pxa2xx_fir_init(MemoryRegion *sysmem,
 
     pxa2xx_fir_reset(s);
 
-    memory_region_init_io(&s->iomem, &pxa2xx_fir_ops, s, "pxa2xx-fir", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_fir_ops, s, "pxa2xx-fir", 0x1000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     if (chr) {
@@ -2027,10 +2027,10 @@ PXA2xxState *pxa270_init(MemoryRegion *address_space,
     s->reset = qemu_allocate_irqs(pxa2xx_reset, s, 1)[0];
 
     /* SDRAM & Internal Memory Storage */
-    memory_region_init_ram(&s->sdram, "pxa270.sdram", sdram_size);
+    memory_region_init_ram(&s->sdram, NULL, "pxa270.sdram", sdram_size);
     vmstate_register_ram_global(&s->sdram);
     memory_region_add_subregion(address_space, PXA2XX_SDRAM_BASE, &s->sdram);
-    memory_region_init_ram(&s->internal, "pxa270.internal", 0x40000);
+    memory_region_init_ram(&s->internal, NULL, "pxa270.internal", 0x40000);
     vmstate_register_ram_global(&s->internal);
     memory_region_add_subregion(address_space, PXA2XX_INTERNAL_BASE,
                                 &s->internal);
@@ -2083,7 +2083,7 @@ PXA2xxState *pxa270_init(MemoryRegion *address_space,
     s->cm_base = 0x41300000;
     s->cm_regs[CCCR >> 2] = 0x02000210;	/* 416.0 MHz */
     s->clkcfg = 0x00000009;		/* Turbo mode active */
-    memory_region_init_io(&s->cm_iomem, &pxa2xx_cm_ops, s, "pxa2xx-cm", 0x1000);
+    memory_region_init_io(&s->cm_iomem, NULL, &pxa2xx_cm_ops, s, "pxa2xx-cm", 0x1000);
     memory_region_add_subregion(address_space, s->cm_base, &s->cm_iomem);
     vmstate_register(NULL, 0, &vmstate_pxa2xx_cm, s);
 
@@ -2093,12 +2093,12 @@ PXA2xxState *pxa270_init(MemoryRegion *address_space,
     s->mm_regs[MDMRS >> 2] = 0x00020002;
     s->mm_regs[MDREFR >> 2] = 0x03ca4000;
     s->mm_regs[MECR >> 2] = 0x00000001;	/* Two PC Card sockets */
-    memory_region_init_io(&s->mm_iomem, &pxa2xx_mm_ops, s, "pxa2xx-mm", 0x1000);
+    memory_region_init_io(&s->mm_iomem, NULL, &pxa2xx_mm_ops, s, "pxa2xx-mm", 0x1000);
     memory_region_add_subregion(address_space, s->mm_base, &s->mm_iomem);
     vmstate_register(NULL, 0, &vmstate_pxa2xx_mm, s);
 
     s->pm_base = 0x40f00000;
-    memory_region_init_io(&s->pm_iomem, &pxa2xx_pm_ops, s, "pxa2xx-pm", 0x100);
+    memory_region_init_io(&s->pm_iomem, NULL, &pxa2xx_pm_ops, s, "pxa2xx-pm", 0x100);
     memory_region_add_subregion(address_space, s->pm_base, &s->pm_iomem);
     vmstate_register(NULL, 0, &vmstate_pxa2xx_pm, s);
 
@@ -2158,10 +2158,10 @@ PXA2xxState *pxa255_init(MemoryRegion *address_space, unsigned int sdram_size)
     s->reset = qemu_allocate_irqs(pxa2xx_reset, s, 1)[0];
 
     /* SDRAM & Internal Memory Storage */
-    memory_region_init_ram(&s->sdram, "pxa255.sdram", sdram_size);
+    memory_region_init_ram(&s->sdram, NULL, "pxa255.sdram", sdram_size);
     vmstate_register_ram_global(&s->sdram);
     memory_region_add_subregion(address_space, PXA2XX_SDRAM_BASE, &s->sdram);
-    memory_region_init_ram(&s->internal, "pxa255.internal",
+    memory_region_init_ram(&s->internal, NULL, "pxa255.internal",
                            PXA2XX_INTERNAL_SIZE);
     vmstate_register_ram_global(&s->internal);
     memory_region_add_subregion(address_space, PXA2XX_INTERNAL_BASE,
@@ -2214,7 +2214,7 @@ PXA2xxState *pxa255_init(MemoryRegion *address_space, unsigned int sdram_size)
     s->cm_base = 0x41300000;
     s->cm_regs[CCCR >> 2] = 0x02000210;	/* 416.0 MHz */
     s->clkcfg = 0x00000009;		/* Turbo mode active */
-    memory_region_init_io(&s->cm_iomem, &pxa2xx_cm_ops, s, "pxa2xx-cm", 0x1000);
+    memory_region_init_io(&s->cm_iomem, NULL, &pxa2xx_cm_ops, s, "pxa2xx-cm", 0x1000);
     memory_region_add_subregion(address_space, s->cm_base, &s->cm_iomem);
     vmstate_register(NULL, 0, &vmstate_pxa2xx_cm, s);
 
@@ -2224,12 +2224,12 @@ PXA2xxState *pxa255_init(MemoryRegion *address_space, unsigned int sdram_size)
     s->mm_regs[MDMRS >> 2] = 0x00020002;
     s->mm_regs[MDREFR >> 2] = 0x03ca4000;
     s->mm_regs[MECR >> 2] = 0x00000001;	/* Two PC Card sockets */
-    memory_region_init_io(&s->mm_iomem, &pxa2xx_mm_ops, s, "pxa2xx-mm", 0x1000);
+    memory_region_init_io(&s->mm_iomem, NULL, &pxa2xx_mm_ops, s, "pxa2xx-mm", 0x1000);
     memory_region_add_subregion(address_space, s->mm_base, &s->mm_iomem);
     vmstate_register(NULL, 0, &vmstate_pxa2xx_mm, s);
 
     s->pm_base = 0x40f00000;
-    memory_region_init_io(&s->pm_iomem, &pxa2xx_pm_ops, s, "pxa2xx-pm", 0x100);
+    memory_region_init_io(&s->pm_iomem, NULL, &pxa2xx_pm_ops, s, "pxa2xx-pm", 0x100);
     memory_region_add_subregion(address_space, s->pm_base, &s->pm_iomem);
     vmstate_register(NULL, 0, &vmstate_pxa2xx_pm, s);
 
diff --git a/hw/arm/pxa2xx_gpio.c b/hw/arm/pxa2xx_gpio.c
index fa31575edd..abf41dc8d7 100644
--- a/hw/arm/pxa2xx_gpio.c
+++ b/hw/arm/pxa2xx_gpio.c
@@ -283,7 +283,7 @@ static int pxa2xx_gpio_initfn(SysBusDevice *dev)
     qdev_init_gpio_in(&dev->qdev, pxa2xx_gpio_set, s->lines);
     qdev_init_gpio_out(&dev->qdev, s->handler, s->lines);
 
-    memory_region_init_io(&s->iomem, &pxa_gpio_ops, s, "pxa2xx-gpio", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pxa_gpio_ops, s, "pxa2xx-gpio", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq0);
     sysbus_init_irq(dev, &s->irq1);
diff --git a/hw/arm/pxa2xx_pic.c b/hw/arm/pxa2xx_pic.c
index 835d07c341..042d4222cb 100644
--- a/hw/arm/pxa2xx_pic.c
+++ b/hw/arm/pxa2xx_pic.c
@@ -278,7 +278,7 @@ DeviceState *pxa2xx_pic_init(hwaddr base, ARMCPU *cpu)
     qdev_init_gpio_in(dev, pxa2xx_pic_set_irq, PXA2XX_PIC_SRCS);
 
     /* Enable IC memory-mapped registers access.  */
-    memory_region_init_io(&s->iomem, &pxa2xx_pic_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_pic_ops, s,
                           "pxa2xx-pic", 0x00100000);
     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
diff --git a/hw/arm/realview.c b/hw/arm/realview.c
index d6f47bf4d4..1e6c1ddf37 100644
--- a/hw/arm/realview.c
+++ b/hw/arm/realview.c
@@ -114,18 +114,18 @@ static void realview_init(QEMUMachineInitArgs *args,
         /* Core tile RAM.  */
         low_ram_size = ram_size - 0x20000000;
         ram_size = 0x20000000;
-        memory_region_init_ram(ram_lo, "realview.lowmem", low_ram_size);
+        memory_region_init_ram(ram_lo, NULL, "realview.lowmem", low_ram_size);
         vmstate_register_ram_global(ram_lo);
         memory_region_add_subregion(sysmem, 0x20000000, ram_lo);
     }
 
-    memory_region_init_ram(ram_hi, "realview.highmem", ram_size);
+    memory_region_init_ram(ram_hi, NULL, "realview.highmem", ram_size);
     vmstate_register_ram_global(ram_hi);
     low_ram_size = ram_size;
     if (low_ram_size > 0x10000000)
       low_ram_size = 0x10000000;
     /* SDRAM at address zero.  */
-    memory_region_init_alias(ram_alias, "realview.alias",
+    memory_region_init_alias(ram_alias, NULL, "realview.alias",
                              ram_hi, 0, low_ram_size);
     memory_region_add_subregion(sysmem, 0, ram_alias);
     if (is_pb) {
@@ -318,7 +318,7 @@ static void realview_init(QEMUMachineInitArgs *args,
        startup code.  I guess this works on real hardware because the
        BootROM happens to be in ROM/flash or in memory that isn't clobbered
        until after Linux boots the secondary CPUs.  */
-    memory_region_init_ram(ram_hack, "realview.hack", 0x1000);
+    memory_region_init_ram(ram_hack, NULL, "realview.hack", 0x1000);
     vmstate_register_ram_global(ram_hack);
     memory_region_add_subregion(sysmem, SMP_BOOT_ADDR, ram_hack);
 
diff --git a/hw/arm/spitz.c b/hw/arm/spitz.c
index b5ed109479..60ad30da57 100644
--- a/hw/arm/spitz.c
+++ b/hw/arm/spitz.c
@@ -169,7 +169,7 @@ static int sl_nand_init(SysBusDevice *dev) {
     nand = drive_get(IF_MTD, 0, 0);
     s->nand = nand_init(nand ? nand->bdrv : NULL, s->manf_id, s->chip_id);
 
-    memory_region_init_io(&s->iomem, &sl_ops, s, "sl", 0x40);
+    memory_region_init_io(&s->iomem, NULL, &sl_ops, s, "sl", 0x40);
     sysbus_init_mmio(dev, &s->iomem);
 
     return 0;
@@ -896,7 +896,7 @@ static void spitz_common_init(QEMUMachineInitArgs *args,
 
     sl_flash_register(mpu, (model == spitz) ? FLASH_128M : FLASH_1024M);
 
-    memory_region_init_ram(rom, "spitz.rom", SPITZ_ROM);
+    memory_region_init_ram(rom, NULL, "spitz.rom", SPITZ_ROM);
     vmstate_register_ram_global(rom);
     memory_region_set_readonly(rom, true);
     memory_region_add_subregion(address_space_mem, 0, rom);
diff --git a/hw/arm/stellaris.c b/hw/arm/stellaris.c
index 2b61e3c7f8..30e7b76594 100644
--- a/hw/arm/stellaris.c
+++ b/hw/arm/stellaris.c
@@ -307,7 +307,7 @@ static int stellaris_gptm_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq);
     qdev_init_gpio_out(&dev->qdev, &s->trigger, 1);
 
-    memory_region_init_io(&s->iomem, &gptm_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &gptm_ops, s,
                           "gptm", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
@@ -669,7 +669,7 @@ static int stellaris_sys_init(uint32_t base, qemu_irq irq,
     s->user0 = macaddr[0] | (macaddr[1] << 8) | (macaddr[2] << 16);
     s->user1 = macaddr[3] | (macaddr[4] << 8) | (macaddr[5] << 16);
 
-    memory_region_init_io(&s->iomem, &ssys_ops, s, "ssys", 0x00001000);
+    memory_region_init_io(&s->iomem, NULL, &ssys_ops, s, "ssys", 0x00001000);
     memory_region_add_subregion(get_system_memory(), base, &s->iomem);
     ssys_reset(s);
     vmstate_register(NULL, -1, &vmstate_stellaris_sys, s);
@@ -862,7 +862,7 @@ static int stellaris_i2c_init(SysBusDevice * dev)
     bus = i2c_init_bus(&dev->qdev, "i2c");
     s->bus = bus;
 
-    memory_region_init_io(&s->iomem, &stellaris_i2c_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &stellaris_i2c_ops, s,
                           "i2c", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     /* ??? For now we only implement the master interface.  */
@@ -1145,7 +1145,7 @@ static int stellaris_adc_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->irq[n]);
     }
 
-    memory_region_init_io(&s->iomem, &stellaris_adc_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &stellaris_adc_ops, s,
                           "adc", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     stellaris_adc_reset(s);
diff --git a/hw/arm/strongarm.c b/hw/arm/strongarm.c
index 4d49306dd0..0f5a545563 100644
--- a/hw/arm/strongarm.c
+++ b/hw/arm/strongarm.c
@@ -173,7 +173,7 @@ static int strongarm_pic_initfn(SysBusDevice *dev)
     StrongARMPICState *s = FROM_SYSBUS(StrongARMPICState, dev);
 
     qdev_init_gpio_in(&dev->qdev, strongarm_pic_set_irq, SA_PIC_SRCS);
-    memory_region_init_io(&s->iomem, &strongarm_pic_ops, s, "pic", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &strongarm_pic_ops, s, "pic", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     sysbus_init_irq(dev, &s->fiq);
@@ -383,7 +383,7 @@ static int strongarm_rtc_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->rtc_irq);
     sysbus_init_irq(dev, &s->rtc_hz_irq);
 
-    memory_region_init_io(&s->iomem, &strongarm_rtc_ops, s, "rtc", 0x10000);
+    memory_region_init_io(&s->iomem, NULL, &strongarm_rtc_ops, s, "rtc", 0x10000);
     sysbus_init_mmio(dev, &s->iomem);
 
     return 0;
@@ -637,7 +637,7 @@ static int strongarm_gpio_initfn(SysBusDevice *dev)
     qdev_init_gpio_in(&dev->qdev, strongarm_gpio_set, 28);
     qdev_init_gpio_out(&dev->qdev, s->handler, 28);
 
-    memory_region_init_io(&s->iomem, &strongarm_gpio_ops, s, "gpio", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &strongarm_gpio_ops, s, "gpio", 0x1000);
 
     sysbus_init_mmio(dev, &s->iomem);
     for (i = 0; i < 11; i++) {
@@ -808,7 +808,7 @@ static int strongarm_ppc_init(SysBusDevice *dev)
     qdev_init_gpio_in(&dev->qdev, strongarm_ppc_set, 22);
     qdev_init_gpio_out(&dev->qdev, s->handler, 22);
 
-    memory_region_init_io(&s->iomem, &strongarm_ppc_ops, s, "ppc", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &strongarm_ppc_ops, s, "ppc", 0x1000);
 
     sysbus_init_mmio(dev, &s->iomem);
 
@@ -1204,7 +1204,7 @@ static int strongarm_uart_init(SysBusDevice *dev)
 {
     StrongARMUARTState *s = FROM_SYSBUS(StrongARMUARTState, dev);
 
-    memory_region_init_io(&s->iomem, &strongarm_uart_ops, s, "uart", 0x10000);
+    memory_region_init_io(&s->iomem, NULL, &strongarm_uart_ops, s, "uart", 0x10000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
 
@@ -1496,7 +1496,7 @@ static int strongarm_ssp_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->iomem, &strongarm_ssp_ops, s, "ssp", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &strongarm_ssp_ops, s, "ssp", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
     s->bus = ssi_create_bus(&dev->qdev, "ssi");
@@ -1571,7 +1571,7 @@ StrongARMState *sa1110_init(MemoryRegion *sysmem,
         exit(1);
     }
 
-    memory_region_init_ram(&s->sdram, "strongarm.sdram", sdram_size);
+    memory_region_init_ram(&s->sdram, NULL, "strongarm.sdram", sdram_size);
     vmstate_register_ram_global(&s->sdram);
     memory_region_add_subregion(sysmem, SA_SDCS0, &s->sdram);
 
diff --git a/hw/arm/tosa.c b/hw/arm/tosa.c
index 47818a5d01..47d1f4ff9b 100644
--- a/hw/arm/tosa.c
+++ b/hw/arm/tosa.c
@@ -222,7 +222,7 @@ static void tosa_init(QEMUMachineInitArgs *args)
 
     mpu = pxa255_init(address_space_mem, tosa_binfo.ram_size);
 
-    memory_region_init_ram(rom, "tosa.rom", TOSA_ROM);
+    memory_region_init_ram(rom, NULL, "tosa.rom", TOSA_ROM);
     vmstate_register_ram_global(rom);
     memory_region_set_readonly(rom, true);
     memory_region_add_subregion(address_space_mem, 0, rom);
diff --git a/hw/arm/versatilepb.c b/hw/arm/versatilepb.c
index 753757ea19..cc0616574d 100644
--- a/hw/arm/versatilepb.c
+++ b/hw/arm/versatilepb.c
@@ -154,7 +154,7 @@ static int vpb_sic_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->parent[i]);
     }
     s->irq = 31;
-    memory_region_init_io(&s->iomem, &vpb_sic_ops, s, "vpb-sic", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &vpb_sic_ops, s, "vpb-sic", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
 }
@@ -193,7 +193,7 @@ static void versatile_init(QEMUMachineInitArgs *args, int board_id)
         fprintf(stderr, "Unable to find CPU definition\n");
         exit(1);
     }
-    memory_region_init_ram(ram, "versatile.ram", args->ram_size);
+    memory_region_init_ram(ram, NULL, "versatile.ram", args->ram_size);
     vmstate_register_ram_global(ram);
     /* ??? RAM should repeat to fill physical memory space.  */
     /* SDRAM at address zero.  */
diff --git a/hw/arm/vexpress.c b/hw/arm/vexpress.c
index a077c62744..710413e5a9 100644
--- a/hw/arm/vexpress.c
+++ b/hw/arm/vexpress.c
@@ -196,7 +196,7 @@ static void a9_daughterboard_init(const VEDBoardInfo *daughterboard,
         exit(1);
     }
 
-    memory_region_init_ram(ram, "vexpress.highmem", ram_size);
+    memory_region_init_ram(ram, NULL, "vexpress.highmem", ram_size);
     vmstate_register_ram_global(ram);
     low_ram_size = ram_size;
     if (low_ram_size > 0x4000000) {
@@ -206,7 +206,7 @@ static void a9_daughterboard_init(const VEDBoardInfo *daughterboard,
      * address space should in theory be remappable to various
      * things including ROM or RAM; we always map the RAM there.
      */
-    memory_region_init_alias(lowram, "vexpress.lowmem", ram, 0, low_ram_size);
+    memory_region_init_alias(lowram, NULL, "vexpress.lowmem", ram, 0, low_ram_size);
     memory_region_add_subregion(sysmem, 0x0, lowram);
     memory_region_add_subregion(sysmem, 0x60000000, ram);
 
@@ -323,7 +323,7 @@ static void a15_daughterboard_init(const VEDBoardInfo *daughterboard,
         }
     }
 
-    memory_region_init_ram(ram, "vexpress.highmem", ram_size);
+    memory_region_init_ram(ram, NULL, "vexpress.highmem", ram_size);
     vmstate_register_ram_global(ram);
     /* RAM is from 0x80000000 upwards; there is no low-memory alias for it. */
     memory_region_add_subregion(sysmem, 0x80000000, ram);
@@ -357,7 +357,7 @@ static void a15_daughterboard_init(const VEDBoardInfo *daughterboard,
     /* 0x2b060000: SP805 watchdog: not modelled */
     /* 0x2b0a0000: PL341 dynamic memory controller: not modelled */
     /* 0x2e000000: system SRAM */
-    memory_region_init_ram(sram, "vexpress.a15sram", 0x10000);
+    memory_region_init_ram(sram, NULL, "vexpress.a15sram", 0x10000);
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(sysmem, 0x2e000000, sram);
 
@@ -491,12 +491,12 @@ static void vexpress_common_init(const VEDBoardInfo *daughterboard,
     }
 
     sram_size = 0x2000000;
-    memory_region_init_ram(sram, "vexpress.sram", sram_size);
+    memory_region_init_ram(sram, NULL, "vexpress.sram", sram_size);
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(sysmem, map[VE_SRAM], sram);
 
     vram_size = 0x800000;
-    memory_region_init_ram(vram, "vexpress.vram", vram_size);
+    memory_region_init_ram(vram, NULL, "vexpress.vram", vram_size);
     vmstate_register_ram_global(vram);
     memory_region_add_subregion(sysmem, map[VE_VIDEORAM], vram);
 
diff --git a/hw/arm/xilinx_zynq.c b/hw/arm/xilinx_zynq.c
index 4602a6f579..0dc0871651 100644
--- a/hw/arm/xilinx_zynq.c
+++ b/hw/arm/xilinx_zynq.c
@@ -132,12 +132,12 @@ static void zynq_init(QEMUMachineInitArgs *args)
     }
 
     /* DDR remapped to address zero.  */
-    memory_region_init_ram(ext_ram, "zynq.ext_ram", ram_size);
+    memory_region_init_ram(ext_ram, NULL, "zynq.ext_ram", ram_size);
     vmstate_register_ram_global(ext_ram);
     memory_region_add_subregion(address_space_mem, 0, ext_ram);
 
     /* 256K of on-chip memory */
-    memory_region_init_ram(ocm_ram, "zynq.ocm_ram", 256 << 10);
+    memory_region_init_ram(ocm_ram, NULL, "zynq.ocm_ram", 256 << 10);
     vmstate_register_ram_global(ocm_ram);
     memory_region_add_subregion(address_space_mem, 0xFFFC0000, ocm_ram);
 
diff --git a/hw/audio/ac97.c b/hw/audio/ac97.c
index baf138b416..47e6f1977b 100644
--- a/hw/audio/ac97.c
+++ b/hw/audio/ac97.c
@@ -1378,8 +1378,8 @@ static int ac97_initfn (PCIDevice *dev)
     c[PCI_INTERRUPT_LINE] = 0x00;      /* intr_ln interrupt line rw */
     c[PCI_INTERRUPT_PIN] = 0x01;      /* intr_pn interrupt pin ro */
 
-    memory_region_init_io (&s->io_nam, &ac97_io_nam_ops, s, "ac97-nam", 1024);
-    memory_region_init_io (&s->io_nabm, &ac97_io_nabm_ops, s, "ac97-nabm", 256);
+    memory_region_init_io (&s->io_nam, NULL, &ac97_io_nam_ops, s, "ac97-nam", 1024);
+    memory_region_init_io (&s->io_nabm, NULL, &ac97_io_nabm_ops, s, "ac97-nabm", 256);
     pci_register_bar (&s->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->io_nam);
     pci_register_bar (&s->dev, 1, PCI_BASE_ADDRESS_SPACE_IO, &s->io_nabm);
     qemu_register_reset (ac97_on_reset, s);
diff --git a/hw/audio/cs4231.c b/hw/audio/cs4231.c
index 2975336057..fb9b700707 100644
--- a/hw/audio/cs4231.c
+++ b/hw/audio/cs4231.c
@@ -144,7 +144,7 @@ static int cs4231_init1(SysBusDevice *dev)
 {
     CSState *s = FROM_SYSBUS(CSState, dev);
 
-    memory_region_init_io(&s->iomem, &cs_mem_ops, s, "cs4321", CS_SIZE);
+    memory_region_init_io(&s->iomem, NULL, &cs_mem_ops, s, "cs4321", CS_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
 
diff --git a/hw/audio/cs4231a.c b/hw/audio/cs4231a.c
index 605dad4988..c31da2ea1b 100644
--- a/hw/audio/cs4231a.c
+++ b/hw/audio/cs4231a.c
@@ -648,7 +648,7 @@ static void cs4231a_initfn (Object *obj)
 {
     CSState *s = CS4231A (obj);
 
-    memory_region_init_io (&s->ioports, &cs_ioport_ops, s, "cs4231a", 4);
+    memory_region_init_io (&s->ioports, NULL, &cs_ioport_ops, s, "cs4231a", 4);
 }
 
 static void cs4231a_realizefn (DeviceState *dev, Error **errp)
diff --git a/hw/audio/es1370.c b/hw/audio/es1370.c
index c1cd169c6c..b953df2d4a 100644
--- a/hw/audio/es1370.c
+++ b/hw/audio/es1370.c
@@ -1035,7 +1035,7 @@ static int es1370_initfn (PCIDevice *dev)
     c[PCI_MIN_GNT] = 0x0c;
     c[PCI_MAX_LAT] = 0x80;
 
-    memory_region_init_io (&s->io, &es1370_io_ops, s, "es1370", 256);
+    memory_region_init_io (&s->io, NULL, &es1370_io_ops, s, "es1370", 256);
     pci_register_bar (&s->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->io);
     qemu_register_reset (es1370_on_reset, s);
 
diff --git a/hw/audio/intel-hda.c b/hw/audio/intel-hda.c
index 3ac90d510d..e94602f59b 100644
--- a/hw/audio/intel-hda.c
+++ b/hw/audio/intel-hda.c
@@ -1135,7 +1135,7 @@ static int intel_hda_init(PCIDevice *pci)
     /* HDCTL off 0x40 bit 0 selects signaling mode (1-HDA, 0 - Ac97) 18.1.19 */
     conf[0x40] = 0x01;
 
-    memory_region_init_io(&d->mmio, &intel_hda_mmio_ops, d,
+    memory_region_init_io(&d->mmio, NULL, &intel_hda_mmio_ops, d,
                           "intel-hda", 0x4000);
     pci_register_bar(&d->pci, 0, 0, &d->mmio);
     if (d->msi) {
diff --git a/hw/audio/marvell_88w8618.c b/hw/audio/marvell_88w8618.c
index c5d88a7841..e04e9325fd 100644
--- a/hw/audio/marvell_88w8618.c
+++ b/hw/audio/marvell_88w8618.c
@@ -244,7 +244,7 @@ static int mv88w8618_audio_init(SysBusDevice *dev)
 
     wm8750_data_req_set(s->wm, mv88w8618_audio_callback, s);
 
-    memory_region_init_io(&s->iomem, &mv88w8618_audio_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &mv88w8618_audio_ops, s,
                           "audio", MP_AUDIO_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/audio/milkymist-ac97.c b/hw/audio/milkymist-ac97.c
index e08e9dca16..79a00fd0d9 100644
--- a/hw/audio/milkymist-ac97.c
+++ b/hw/audio/milkymist-ac97.c
@@ -300,7 +300,7 @@ static int milkymist_ac97_init(SysBusDevice *dev)
     s->voice_out = AUD_open_out(&s->card, s->voice_out,
             "mm_ac97.out", s, ac97_out_cb, &as);
 
-    memory_region_init_io(&s->regs_region, &ac97_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &ac97_mmio_ops, s,
             "milkymist-ac97", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/audio/pcspk.c b/hw/audio/pcspk.c
index 5dde0e75da..123793b3e3 100644
--- a/hw/audio/pcspk.c
+++ b/hw/audio/pcspk.c
@@ -167,7 +167,7 @@ static void pcspk_initfn(Object *obj)
 {
     PCSpkState *s = PC_SPEAKER(obj);
 
-    memory_region_init_io(&s->ioport, &pcspk_io_ops, s, "elcr", 1);
+    memory_region_init_io(&s->ioport, NULL, &pcspk_io_ops, s, "elcr", 1);
 }
 
 static void pcspk_realizefn(DeviceState *dev, Error **errp)
diff --git a/hw/audio/pl041.c b/hw/audio/pl041.c
index 653ab4fbb4..5dd18c7d9d 100644
--- a/hw/audio/pl041.c
+++ b/hw/audio/pl041.c
@@ -543,7 +543,7 @@ static int pl041_init(SysBusDevice *dev)
     }
 
     /* Connect the device to the sysbus */
-    memory_region_init_io(&s->iomem, &pl041_ops, s, "pl041", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl041_ops, s, "pl041", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
 
diff --git a/hw/block/fdc.c b/hw/block/fdc.c
index 930f191d9e..1bec805e04 100644
--- a/hw/block/fdc.c
+++ b/hw/block/fdc.c
@@ -2149,7 +2149,7 @@ static int sysbus_fdc_init1(SysBusDevice *dev)
     FDCtrl *fdctrl = &sys->state;
     int ret;
 
-    memory_region_init_io(&fdctrl->iomem, &fdctrl_mem_ops, fdctrl, "fdc", 0x08);
+    memory_region_init_io(&fdctrl->iomem, NULL, &fdctrl_mem_ops, fdctrl, "fdc", 0x08);
     sysbus_init_mmio(dev, &fdctrl->iomem);
     sysbus_init_irq(dev, &fdctrl->irq);
     qdev_init_gpio_in(&dev->qdev, fdctrl_handle_tc, 1);
@@ -2165,7 +2165,7 @@ static int sun4m_fdc_init1(SysBusDevice *dev)
 {
     FDCtrl *fdctrl = &(FROM_SYSBUS(FDCtrlSysBus, dev)->state);
 
-    memory_region_init_io(&fdctrl->iomem, &fdctrl_mem_strict_ops, fdctrl,
+    memory_region_init_io(&fdctrl->iomem, NULL, &fdctrl_mem_strict_ops, fdctrl,
                           "fdctrl", 0x08);
     sysbus_init_mmio(dev, &fdctrl->iomem);
     sysbus_init_irq(dev, &fdctrl->irq);
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 58b0d91d0a..aa3d9a9062 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -777,7 +777,7 @@ static int nvme_init(PCIDevice *pci_dev)
     n->sq = g_malloc0(sizeof(*n->sq)*n->num_queues);
     n->cq = g_malloc0(sizeof(*n->cq)*n->num_queues);
 
-    memory_region_init_io(&n->iomem, &nvme_mmio_ops, n, "nvme", n->reg_size);
+    memory_region_init_io(&n->iomem, NULL, &nvme_mmio_ops, n, "nvme", n->reg_size);
     pci_register_bar(&n->parent_obj, 0,
         PCI_BASE_ADDRESS_SPACE_MEMORY | PCI_BASE_ADDRESS_MEM_TYPE_64,
         &n->iomem);
diff --git a/hw/block/onenand.c b/hw/block/onenand.c
index 8b511a79dc..edbce3c707 100644
--- a/hw/block/onenand.c
+++ b/hw/block/onenand.c
@@ -113,9 +113,9 @@ static void onenand_mem_setup(OneNANDState *s)
     /* XXX: We should use IO_MEM_ROMD but we broke it earlier...
      * Both 0x0000 ... 0x01ff and 0x8000 ... 0x800f can be used to
      * write boot commands.  Also take note of the BWPS bit.  */
-    memory_region_init(&s->container, "onenand", 0x10000 << s->shift);
+    memory_region_init(&s->container, NULL, "onenand", 0x10000 << s->shift);
     memory_region_add_subregion(&s->container, 0, &s->iomem);
-    memory_region_init_alias(&s->mapped_ram, "onenand-mapped-ram",
+    memory_region_init_alias(&s->mapped_ram, NULL, "onenand-mapped-ram",
                              &s->ram, 0x0200 << s->shift,
                              0xbe00 << s->shift);
     memory_region_add_subregion_overlap(&s->container,
@@ -768,7 +768,7 @@ static int onenand_initfn(SysBusDevice *dev)
     s->blockwp = g_malloc(s->blocks);
     s->density_mask = (s->id.dev & 0x08)
         ? (1 << (6 + ((s->id.dev >> 4) & 7))) : 0;
-    memory_region_init_io(&s->iomem, &onenand_ops, s, "onenand",
+    memory_region_init_io(&s->iomem, NULL, &onenand_ops, s, "onenand",
                           0x10000 << s->shift);
     if (!s->bdrv) {
         s->image = memset(g_malloc(size + (size >> 5)),
@@ -782,7 +782,7 @@ static int onenand_initfn(SysBusDevice *dev)
     }
     s->otp = memset(g_malloc((64 + 2) << PAGE_SHIFT),
                     0xff, (64 + 2) << PAGE_SHIFT);
-    memory_region_init_ram(&s->ram, "onenand.ram", 0xc000 << s->shift);
+    memory_region_init_ram(&s->ram, NULL, "onenand.ram", 0xc000 << s->shift);
     vmstate_register_ram_global(&s->ram);
     ram = memory_region_get_ram_ptr(&s->ram);
     s->boot[0] = ram + (0x0000 << s->shift);
diff --git a/hw/block/pc_sysfw.c b/hw/block/pc_sysfw.c
index 412d1b0f77..0669410cfc 100644
--- a/hw/block/pc_sysfw.c
+++ b/hw/block/pc_sysfw.c
@@ -59,7 +59,7 @@ static void pc_isa_bios_init(MemoryRegion *rom_memory,
         isa_bios_size = 128 * 1024;
     }
     isa_bios = g_malloc(sizeof(*isa_bios));
-    memory_region_init_ram(isa_bios, "isa-bios", isa_bios_size);
+    memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size);
     vmstate_register_ram_global(isa_bios);
     memory_region_add_subregion_overlap(rom_memory,
                                         0x100000 - isa_bios_size,
@@ -162,7 +162,7 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw)
         goto bios_error;
     }
     bios = g_malloc(sizeof(*bios));
-    memory_region_init_ram(bios, "pc.bios", bios_size);
+    memory_region_init_ram(bios, NULL, "pc.bios", bios_size);
     vmstate_register_ram_global(bios);
     if (!isapc_ram_fw) {
         memory_region_set_readonly(bios, true);
@@ -183,7 +183,7 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw)
         isa_bios_size = 128 * 1024;
     }
     isa_bios = g_malloc(sizeof(*isa_bios));
-    memory_region_init_alias(isa_bios, "isa-bios", bios,
+    memory_region_init_alias(isa_bios, NULL, "isa-bios", bios,
                              bios_size - isa_bios_size, isa_bios_size);
     memory_region_add_subregion_overlap(rom_memory,
                                         0x100000 - isa_bios_size,
diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c
index 63d7c9951f..5d51e584e5 100644
--- a/hw/block/pflash_cfi01.c
+++ b/hw/block/pflash_cfi01.c
@@ -579,7 +579,8 @@ static int pflash_cfi01_init(SysBusDevice *dev)
 #endif
 
     memory_region_init_rom_device(
-        &pfl->mem, pfl->be ? &pflash_cfi01_ops_be : &pflash_cfi01_ops_le, pfl,
+        &pfl->mem, NULL,
+        pfl->be ? &pflash_cfi01_ops_be : &pflash_cfi01_ops_le, pfl,
         pfl->name, total_len);
     vmstate_register_ram(&pfl->mem, DEVICE(pfl));
     pfl->storage = memory_region_get_ram_ptr(&pfl->mem);
diff --git a/hw/block/pflash_cfi02.c b/hw/block/pflash_cfi02.c
index 5f25246926..8c1d57097e 100644
--- a/hw/block/pflash_cfi02.c
+++ b/hw/block/pflash_cfi02.c
@@ -100,10 +100,10 @@ static void pflash_setup_mappings(pflash_t *pfl)
     unsigned i;
     hwaddr size = memory_region_size(&pfl->orig_mem);
 
-    memory_region_init(&pfl->mem, "pflash", pfl->mappings * size);
+    memory_region_init(&pfl->mem, NULL, "pflash", pfl->mappings * size);
     pfl->mem_mappings = g_new(MemoryRegion, pfl->mappings);
     for (i = 0; i < pfl->mappings; ++i) {
-        memory_region_init_alias(&pfl->mem_mappings[i], "pflash-alias",
+        memory_region_init_alias(&pfl->mem_mappings[i], NULL, "pflash-alias",
                                  &pfl->orig_mem, 0, size);
         memory_region_add_subregion(&pfl->mem, i * size, &pfl->mem_mappings[i]);
     }
@@ -600,7 +600,7 @@ static int pflash_cfi02_init(SysBusDevice *dev)
         return NULL;
 #endif
 
-    memory_region_init_rom_device(&pfl->orig_mem, pfl->be ?
+    memory_region_init_rom_device(&pfl->orig_mem, NULL, pfl->be ?
                                   &pflash_cfi02_ops_be : &pflash_cfi02_ops_le,
                                   pfl, pfl->name, chip_len);
     vmstate_register_ram(&pfl->orig_mem, DEVICE(pfl));
diff --git a/hw/char/cadence_uart.c b/hw/char/cadence_uart.c
index 205e125de9..36e8cd5f6f 100644
--- a/hw/char/cadence_uart.c
+++ b/hw/char/cadence_uart.c
@@ -442,7 +442,7 @@ static int cadence_uart_init(SysBusDevice *dev)
 {
     UartState *s = FROM_SYSBUS(UartState, dev);
 
-    memory_region_init_io(&s->iomem, &uart_ops, s, "uart", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &uart_ops, s, "uart", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
 
diff --git a/hw/char/debugcon.c b/hw/char/debugcon.c
index f254841aec..c62feadd64 100644
--- a/hw/char/debugcon.c
+++ b/hw/char/debugcon.c
@@ -103,7 +103,7 @@ static void debugcon_isa_realizefn(DeviceState *dev, Error **errp)
         error_propagate(errp, err);
         return;
     }
-    memory_region_init_io(&s->io, &debugcon_ops, s,
+    memory_region_init_io(&s->io, NULL, &debugcon_ops, s,
                           TYPE_ISA_DEBUGCON_DEVICE, 1);
     memory_region_add_subregion(isa_address_space_io(d),
                                 isa->iobase, &s->io);
diff --git a/hw/char/escc.c b/hw/char/escc.c
index c2cb07f3bd..29ecbaa462 100644
--- a/hw/char/escc.c
+++ b/hw/char/escc.c
@@ -886,7 +886,7 @@ static int escc_init1(SysBusDevice *dev)
     s->chn[0].otherchn = &s->chn[1];
     s->chn[1].otherchn = &s->chn[0];
 
-    memory_region_init_io(&s->mmio, &escc_mem_ops, s, "escc",
+    memory_region_init_io(&s->mmio, NULL, &escc_mem_ops, s, "escc",
                           ESCC_SIZE << s->it_shift);
     sysbus_init_mmio(dev, &s->mmio);
 
diff --git a/hw/char/etraxfs_ser.c b/hw/char/etraxfs_ser.c
index 11820f5864..ffd9767a52 100644
--- a/hw/char/etraxfs_ser.c
+++ b/hw/char/etraxfs_ser.c
@@ -211,7 +211,7 @@ static int etraxfs_ser_init(SysBusDevice *dev)
     struct etrax_serial *s = FROM_SYSBUS(typeof (*s), dev);
 
     sysbus_init_irq(dev, &s->irq);
-    memory_region_init_io(&s->mmio, &ser_ops, s, "etraxfs-serial", R_MAX * 4);
+    memory_region_init_io(&s->mmio, NULL, &ser_ops, s, "etraxfs-serial", R_MAX * 4);
     sysbus_init_mmio(dev, &s->mmio);
 
     s->chr = qemu_char_get_next_serial();
diff --git a/hw/char/exynos4210_uart.c b/hw/char/exynos4210_uart.c
index 5751816c62..b879ba4a56 100644
--- a/hw/char/exynos4210_uart.c
+++ b/hw/char/exynos4210_uart.c
@@ -630,7 +630,7 @@ static int exynos4210_uart_init(SysBusDevice *dev)
     Exynos4210UartState *s = FROM_SYSBUS(Exynos4210UartState, dev);
 
     /* memory mapping */
-    memory_region_init_io(&s->iomem, &exynos4210_uart_ops, s, "exynos4210.uart",
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_uart_ops, s, "exynos4210.uart",
                           EXYNOS4210_UART_REGS_MEM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/char/grlib_apbuart.c b/hw/char/grlib_apbuart.c
index a64453fb18..a1587dc5fd 100644
--- a/hw/char/grlib_apbuart.c
+++ b/hw/char/grlib_apbuart.c
@@ -242,7 +242,7 @@ static int grlib_apbuart_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &uart->irq);
 
-    memory_region_init_io(&uart->iomem, &grlib_apbuart_ops, uart,
+    memory_region_init_io(&uart->iomem, NULL, &grlib_apbuart_ops, uart,
                           "uart", UART_REG_SIZE);
 
     sysbus_init_mmio(dev, &uart->iomem);
diff --git a/hw/char/imx_serial.c b/hw/char/imx_serial.c
index 2a2c230c55..9fa4da7634 100644
--- a/hw/char/imx_serial.c
+++ b/hw/char/imx_serial.c
@@ -386,7 +386,7 @@ static int imx_serial_init(SysBusDevice *dev)
     IMXSerialState *s = FROM_SYSBUS(IMXSerialState, dev);
 
 
-    memory_region_init_io(&s->iomem, &imx_serial_ops, s, "imx-serial", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &imx_serial_ops, s, "imx-serial", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
 
diff --git a/hw/char/lm32_uart.c b/hw/char/lm32_uart.c
index 99721ab78d..e8fdbe4339 100644
--- a/hw/char/lm32_uart.c
+++ b/hw/char/lm32_uart.c
@@ -250,7 +250,7 @@ static int lm32_uart_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->iomem, &uart_ops, s, "uart", R_MAX * 4);
+    memory_region_init_io(&s->iomem, NULL, &uart_ops, s, "uart", R_MAX * 4);
     sysbus_init_mmio(dev, &s->iomem);
 
     s->chr = qemu_char_get_next_serial();
diff --git a/hw/char/mcf_uart.c b/hw/char/mcf_uart.c
index 3ec4705867..98fd44e66a 100644
--- a/hw/char/mcf_uart.c
+++ b/hw/char/mcf_uart.c
@@ -302,6 +302,6 @@ void mcf_uart_mm_init(MemoryRegion *sysmem,
     mcf_uart_state *s;
 
     s = mcf_uart_init(irq, chr);
-    memory_region_init_io(&s->iomem, &mcf_uart_ops, s, "uart", 0x40);
+    memory_region_init_io(&s->iomem, NULL, &mcf_uart_ops, s, "uart", 0x40);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 }
diff --git a/hw/char/milkymist-uart.c b/hw/char/milkymist-uart.c
index cbc7d73a6e..22faf4c168 100644
--- a/hw/char/milkymist-uart.c
+++ b/hw/char/milkymist-uart.c
@@ -196,7 +196,7 @@ static int milkymist_uart_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->regs_region, &uart_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &uart_mmio_ops, s,
             "milkymist-uart", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/char/omap_uart.c b/hw/char/omap_uart.c
index 5bb36ed2c1..0b91693602 100644
--- a/hw/char/omap_uart.c
+++ b/hw/char/omap_uart.c
@@ -168,7 +168,7 @@ struct omap_uart_s *omap2_uart_init(MemoryRegion *sysmem,
     struct omap_uart_s *s = omap_uart_init(base, irq,
                     fclk, iclk, txdma, rxdma, label, chr);
 
-    memory_region_init_io(&s->iomem, &omap_uart_ops, s, "omap.uart", 0x100);
+    memory_region_init_io(&s->iomem, NULL, &omap_uart_ops, s, "omap.uart", 0x100);
 
     s->ta = ta;
 
diff --git a/hw/char/parallel.c b/hw/char/parallel.c
index caa9eb4de4..ad96ea59c6 100644
--- a/hw/char/parallel.c
+++ b/hw/char/parallel.c
@@ -587,7 +587,7 @@ bool parallel_mm_init(MemoryRegion *address_space,
     s->it_shift = it_shift;
     qemu_register_reset(parallel_reset, s);
 
-    memory_region_init_io(&s->iomem, &parallel_mm_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &parallel_mm_ops, s,
                           "parallel", 8 << it_shift);
     memory_region_add_subregion(address_space, base, &s->iomem);
     return true;
diff --git a/hw/char/pl011.c b/hw/char/pl011.c
index 7079ef6be1..bd26e6d871 100644
--- a/hw/char/pl011.c
+++ b/hw/char/pl011.c
@@ -265,7 +265,7 @@ static int pl011_init(SysBusDevice *dev, const unsigned char *id)
 {
     pl011_state *s = FROM_SYSBUS(pl011_state, dev);
 
-    memory_region_init_io(&s->iomem, &pl011_ops, s, "pl011", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl011_ops, s, "pl011", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     s->id = id;
diff --git a/hw/char/serial-isa.c b/hw/char/serial-isa.c
index e06a802e24..0bce75bcb7 100644
--- a/hw/char/serial-isa.c
+++ b/hw/char/serial-isa.c
@@ -72,7 +72,7 @@ static void serial_isa_realizefn(DeviceState *dev, Error **errp)
     serial_realize_core(s, errp);
     qdev_set_legacy_instance_id(dev, isa->iobase, 3);
 
-    memory_region_init_io(&s->io, &serial_io_ops, s, "serial", 8);
+    memory_region_init_io(&s->io, NULL, &serial_io_ops, s, "serial", 8);
     isa_register_ioport(isadev, &s->io, isa->iobase);
 }
 
diff --git a/hw/char/serial-pci.c b/hw/char/serial-pci.c
index 3bec8ebe7b..6adfbe6699 100644
--- a/hw/char/serial-pci.c
+++ b/hw/char/serial-pci.c
@@ -63,7 +63,7 @@ static int serial_pci_init(PCIDevice *dev)
     pci->dev.config[PCI_INTERRUPT_PIN] = 0x01;
     s->irq = pci->dev.irq[0];
 
-    memory_region_init_io(&s->io, &serial_io_ops, s, "serial", 8);
+    memory_region_init_io(&s->io, NULL, &serial_io_ops, s, "serial", 8);
     pci_register_bar(&pci->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->io);
     return 0;
 }
@@ -102,7 +102,7 @@ static int multi_serial_pci_init(PCIDevice *dev)
     assert(pci->ports <= PCI_SERIAL_MAX_PORTS);
 
     pci->dev.config[PCI_INTERRUPT_PIN] = 0x01;
-    memory_region_init(&pci->iobar, "multiserial", 8 * pci->ports);
+    memory_region_init(&pci->iobar, NULL, "multiserial", 8 * pci->ports);
     pci_register_bar(&pci->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &pci->iobar);
     pci->irqs = qemu_allocate_irqs(multi_serial_irq_mux, pci,
                                    pci->ports);
@@ -118,7 +118,7 @@ static int multi_serial_pci_init(PCIDevice *dev)
         }
         s->irq = pci->irqs[i];
         pci->name[i] = g_strdup_printf("uart #%d", i+1);
-        memory_region_init_io(&s->io, &serial_io_ops, s, pci->name[i], 8);
+        memory_region_init_io(&s->io, NULL, &serial_io_ops, s, pci->name[i], 8);
         memory_region_add_subregion(&pci->iobar, 8 * i, &s->io);
     }
     return 0;
diff --git a/hw/char/serial.c b/hw/char/serial.c
index 6382f98389..602559254e 100644
--- a/hw/char/serial.c
+++ b/hw/char/serial.c
@@ -703,7 +703,7 @@ SerialState *serial_init(int base, qemu_irq irq, int baudbase,
 
     vmstate_register(NULL, base, &vmstate_serial, s);
 
-    memory_region_init_io(&s->io, &serial_io_ops, s, "serial", 8);
+    memory_region_init_io(&s->io, NULL, &serial_io_ops, s, "serial", 8);
     memory_region_add_subregion(system_io, base, &s->io);
 
     return s;
@@ -766,7 +766,7 @@ SerialState *serial_mm_init(MemoryRegion *address_space,
     }
     vmstate_register(NULL, base, &vmstate_serial, s);
 
-    memory_region_init_io(&s->io, &serial_mm_ops[end], s,
+    memory_region_init_io(&s->io, NULL, &serial_mm_ops[end], s,
                           "serial", 8 << it_shift);
     memory_region_add_subregion(address_space, base, &s->io);
 
diff --git a/hw/char/sh_serial.c b/hw/char/sh_serial.c
index b3286438ca..6223a557b2 100644
--- a/hw/char/sh_serial.c
+++ b/hw/char/sh_serial.c
@@ -383,14 +383,14 @@ void sh_serial_init(MemoryRegion *sysmem,
 
     sh_serial_clear_fifo(s);
 
-    memory_region_init_io(&s->iomem, &sh_serial_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &sh_serial_ops, s,
                           "serial", 0x100000000ULL);
 
-    memory_region_init_alias(&s->iomem_p4, "serial-p4", &s->iomem,
+    memory_region_init_alias(&s->iomem_p4, NULL, "serial-p4", &s->iomem,
                              0, 0x28);
     memory_region_add_subregion(sysmem, P4ADDR(base), &s->iomem_p4);
 
-    memory_region_init_alias(&s->iomem_a7, "serial-a7", &s->iomem,
+    memory_region_init_alias(&s->iomem_a7, NULL, "serial-a7", &s->iomem,
                              0, 0x28);
     memory_region_add_subregion(sysmem, A7ADDR(base), &s->iomem_a7);
 
diff --git a/hw/char/tpci200.c b/hw/char/tpci200.c
index 01706020be..9174042df4 100644
--- a/hw/char/tpci200.c
+++ b/hw/char/tpci200.c
@@ -588,17 +588,17 @@ static int tpci200_initfn(PCIDevice *pci_dev)
     pci_set_long(c + 0x48, 0x00024C06);
     pci_set_long(c + 0x4C, 0x00000003);
 
-    memory_region_init_io(&s->mmio, &tpci200_cfg_ops,
+    memory_region_init_io(&s->mmio, NULL, &tpci200_cfg_ops,
                           s, "tpci200_mmio", 128);
-    memory_region_init_io(&s->io,   &tpci200_cfg_ops,
+    memory_region_init_io(&s->io, NULL,   &tpci200_cfg_ops,
                           s, "tpci200_io",   128);
-    memory_region_init_io(&s->las0, &tpci200_las0_ops,
+    memory_region_init_io(&s->las0, NULL, &tpci200_las0_ops,
                           s, "tpci200_las0", 256);
-    memory_region_init_io(&s->las1, &tpci200_las1_ops,
+    memory_region_init_io(&s->las1, NULL, &tpci200_las1_ops,
                           s, "tpci200_las1", 1024);
-    memory_region_init_io(&s->las2, &tpci200_las2_ops,
+    memory_region_init_io(&s->las2, NULL, &tpci200_las2_ops,
                           s, "tpci200_las2", 1024*1024*32);
-    memory_region_init_io(&s->las3, &tpci200_las3_ops,
+    memory_region_init_io(&s->las3, NULL, &tpci200_las3_ops,
                           s, "tpci200_las3", 1024*1024*16);
     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->mmio);
     pci_register_bar(&s->dev, 1, PCI_BASE_ADDRESS_SPACE_IO,     &s->io);
diff --git a/hw/char/xilinx_uartlite.c b/hw/char/xilinx_uartlite.c
index 3f7e989f35..241bf1f448 100644
--- a/hw/char/xilinx_uartlite.c
+++ b/hw/char/xilinx_uartlite.c
@@ -199,7 +199,7 @@ static int xilinx_uartlite_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq);
 
     uart_update_status(s);
-    memory_region_init_io(&s->mmio, &uart_ops, s, "xlnx.xps-uartlite",
+    memory_region_init_io(&s->mmio, NULL, &uart_ops, s, "xlnx.xps-uartlite",
                                                                 R_MAX * 4);
     sysbus_init_mmio(dev, &s->mmio);
 
diff --git a/hw/core/empty_slot.c b/hw/core/empty_slot.c
index 5234a4ddc6..35e32f90f9 100644
--- a/hw/core/empty_slot.c
+++ b/hw/core/empty_slot.c
@@ -70,7 +70,7 @@ static int empty_slot_init1(SysBusDevice *dev)
 {
     EmptySlot *s = FROM_SYSBUS(EmptySlot, dev);
 
-    memory_region_init_io(&s->iomem, &empty_slot_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &empty_slot_ops, s,
                           "empty-slot", s->size);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
diff --git a/hw/cpu/a15mpcore.c b/hw/cpu/a15mpcore.c
index 648656d5b4..773c83a382 100644
--- a/hw/cpu/a15mpcore.c
+++ b/hw/cpu/a15mpcore.c
@@ -68,7 +68,7 @@ static int a15mp_priv_init(SysBusDevice *dev)
      *  0x5000-0x5fff -- GIC virtual interface control (not modelled)
      *  0x6000-0x7fff -- GIC virtual CPU interface (not modelled)
      */
-    memory_region_init(&s->container, "a15mp-priv-container", 0x8000);
+    memory_region_init(&s->container, NULL, "a15mp-priv-container", 0x8000);
     memory_region_add_subregion(&s->container, 0x1000,
                                 sysbus_mmio_get_region(busdev, 0));
     memory_region_add_subregion(&s->container, 0x2000,
diff --git a/hw/cpu/a9mpcore.c b/hw/cpu/a9mpcore.c
index 0a1a10f37a..26a3858351 100644
--- a/hw/cpu/a9mpcore.c
+++ b/hw/cpu/a9mpcore.c
@@ -71,7 +71,7 @@ static int a9mp_priv_init(SysBusDevice *dev)
      *
      * We should implement the global timer but don't currently do so.
      */
-    memory_region_init(&s->container, "a9mp-priv-container", 0x2000);
+    memory_region_init(&s->container, NULL, "a9mp-priv-container", 0x2000);
     memory_region_add_subregion(&s->container, 0,
                                 sysbus_mmio_get_region(scubusdev, 0));
     /* GIC CPU interface */
diff --git a/hw/cpu/arm11mpcore.c b/hw/cpu/arm11mpcore.c
index 90dceade71..67e2828603 100644
--- a/hw/cpu/arm11mpcore.c
+++ b/hw/cpu/arm11mpcore.c
@@ -87,8 +87,8 @@ static void mpcore_priv_map_setup(ARM11MPCorePriveState *s)
     SysBusDevice *gicbusdev = SYS_BUS_DEVICE(s->gic);
     SysBusDevice *timerbusdev = SYS_BUS_DEVICE(s->mptimer);
     SysBusDevice *wdtbusdev = SYS_BUS_DEVICE(s->wdtimer);
-    memory_region_init(&s->container, "mpcode-priv-container", 0x2000);
-    memory_region_init_io(&s->iomem, &mpcore_scu_ops, s, "mpcore-scu", 0x100);
+    memory_region_init(&s->container, NULL, "mpcode-priv-container", 0x2000);
+    memory_region_init_io(&s->iomem, NULL, &mpcore_scu_ops, s, "mpcore-scu", 0x100);
     memory_region_add_subregion(&s->container, 0, &s->iomem);
     /* GIC CPU interfaces: "current CPU" at 0x100, then specific CPUs
      * at 0x200, 0x300...
diff --git a/hw/cpu/icc_bus.c b/hw/cpu/icc_bus.c
index 73a1dc985f..9e901e95b3 100644
--- a/hw/cpu/icc_bus.c
+++ b/hw/cpu/icc_bus.c
@@ -95,7 +95,7 @@ static void icc_bridge_init(Object *obj)
     /* Do not change order of registering regions,
      * APIC must be first registered region, board maps it by 0 index
      */
-    memory_region_init(&s->apic_container, "icc-apic-container",
+    memory_region_init(&s->apic_container, NULL, "icc-apic-container",
                        APIC_SPACE_SIZE);
     sysbus_init_mmio(sb, &s->apic_container);
     s->icc_bus.apic_address_space = &s->apic_container;
diff --git a/hw/cris/axis_dev88.c b/hw/cris/axis_dev88.c
index 7475671308..9104d6194f 100644
--- a/hw/cris/axis_dev88.c
+++ b/hw/cris/axis_dev88.c
@@ -269,13 +269,13 @@ void axisdev88_init(QEMUMachineInitArgs *args)
     env = &cpu->env;
 
     /* allocate RAM */
-    memory_region_init_ram(phys_ram, "axisdev88.ram", ram_size);
+    memory_region_init_ram(phys_ram, NULL, "axisdev88.ram", ram_size);
     vmstate_register_ram_global(phys_ram);
     memory_region_add_subregion(address_space_mem, 0x40000000, phys_ram);
 
     /* The ETRAX-FS has 128Kb on chip ram, the docs refer to it as the 
        internal memory.  */
-    memory_region_init_ram(phys_intmem, "axisdev88.chipram", INTMEM_SIZE);
+    memory_region_init_ram(phys_intmem, NULL, "axisdev88.chipram", INTMEM_SIZE);
     vmstate_register_ram_global(phys_intmem);
     memory_region_add_subregion(address_space_mem, 0x38000000, phys_intmem);
 
@@ -283,13 +283,13 @@ void axisdev88_init(QEMUMachineInitArgs *args)
     nand = drive_get(IF_MTD, 0, 0);
     nand_state.nand = nand_init(nand ? nand->bdrv : NULL,
                                 NAND_MFR_STMICRO, 0x39);
-    memory_region_init_io(&nand_state.iomem, &nand_ops, &nand_state,
+    memory_region_init_io(&nand_state.iomem, NULL, &nand_ops, &nand_state,
                           "nand", 0x05000000);
     memory_region_add_subregion(address_space_mem, 0x10000000,
                                 &nand_state.iomem);
 
     gpio_state.nand = &nand_state;
-    memory_region_init_io(&gpio_state.iomem, &gpio_ops, &gpio_state,
+    memory_region_init_io(&gpio_state.iomem, NULL, &gpio_ops, &gpio_state,
                           "gpio", 0x5c);
     memory_region_add_subregion(address_space_mem, 0x3001a000,
                                 &gpio_state.iomem);
diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c
index 0d9eee876a..00ac9a383c 100644
--- a/hw/display/cirrus_vga.c
+++ b/hw/display/cirrus_vga.c
@@ -2840,21 +2840,21 @@ static void cirrus_init_common(CirrusVGAState * s, int device_id, int is_pci,
     }
 
     /* Register ioport 0x3b0 - 0x3df */
-    memory_region_init_io(&s->cirrus_vga_io, &cirrus_vga_io_ops, s,
+    memory_region_init_io(&s->cirrus_vga_io, NULL, &cirrus_vga_io_ops, s,
                           "cirrus-io", 0x30);
     memory_region_add_subregion(system_io, 0x3b0, &s->cirrus_vga_io);
 
-    memory_region_init(&s->low_mem_container,
+    memory_region_init(&s->low_mem_container, NULL,
                        "cirrus-lowmem-container",
                        0x20000);
 
-    memory_region_init_io(&s->low_mem, &cirrus_vga_mem_ops, s,
+    memory_region_init_io(&s->low_mem, NULL, &cirrus_vga_mem_ops, s,
                           "cirrus-low-memory", 0x20000);
     memory_region_add_subregion(&s->low_mem_container, 0, &s->low_mem);
     for (i = 0; i < 2; ++i) {
         static const char *names[] = { "vga.bank0", "vga.bank1" };
         MemoryRegion *bank = &s->cirrus_bank[i];
-        memory_region_init_alias(bank, names[i], &s->vga.vram, 0, 0x8000);
+        memory_region_init_alias(bank, NULL, names[i], &s->vga.vram, 0, 0x8000);
         memory_region_set_enabled(bank, false);
         memory_region_add_subregion_overlap(&s->low_mem_container, i * 0x8000,
                                             bank, 1);
@@ -2866,13 +2866,13 @@ static void cirrus_init_common(CirrusVGAState * s, int device_id, int is_pci,
     memory_region_set_coalescing(&s->low_mem);
 
     /* I/O handler for LFB */
-    memory_region_init_io(&s->cirrus_linear_io, &cirrus_linear_io_ops, s,
+    memory_region_init_io(&s->cirrus_linear_io, NULL, &cirrus_linear_io_ops, s,
                           "cirrus-linear-io", s->vga.vram_size_mb
                                               * 1024 * 1024);
     memory_region_set_flush_coalesced(&s->cirrus_linear_io);
 
     /* I/O handler for LFB */
-    memory_region_init_io(&s->cirrus_linear_bitblt_io,
+    memory_region_init_io(&s->cirrus_linear_bitblt_io, NULL,
                           &cirrus_linear_bitblt_io_ops,
                           s,
                           "cirrus-bitblt-mmio",
@@ -2880,7 +2880,7 @@ static void cirrus_init_common(CirrusVGAState * s, int device_id, int is_pci,
     memory_region_set_flush_coalesced(&s->cirrus_linear_bitblt_io);
 
     /* I/O handler for memory-mapped I/O */
-    memory_region_init_io(&s->cirrus_mmio_io, &cirrus_mmio_io_ops, s,
+    memory_region_init_io(&s->cirrus_mmio_io, NULL, &cirrus_mmio_io_ops, s,
                           "cirrus-mmio", CIRRUS_PNPMMIO_SIZE);
     memory_region_set_flush_coalesced(&s->cirrus_mmio_io);
 
@@ -2965,7 +2965,7 @@ static int pci_cirrus_vga_initfn(PCIDevice *dev)
 
      /* setup PCI */
 
-    memory_region_init(&s->pci_bar, "cirrus-pci-bar0", 0x2000000);
+    memory_region_init(&s->pci_bar, NULL, "cirrus-pci-bar0", 0x2000000);
 
     /* XXX: add byte swapping apertures */
     memory_region_add_subregion(&s->pci_bar, 0, &s->cirrus_linear_io);
diff --git a/hw/display/exynos4210_fimd.c b/hw/display/exynos4210_fimd.c
index 0da00a9f96..d9088d9594 100644
--- a/hw/display/exynos4210_fimd.c
+++ b/hw/display/exynos4210_fimd.c
@@ -1902,7 +1902,7 @@ static int exynos4210_fimd_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq[1]);
     sysbus_init_irq(dev, &s->irq[2]);
 
-    memory_region_init_io(&s->iomem, &exynos4210_fimd_mmio_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_fimd_mmio_ops, s,
             "exynos4210.fimd", FIMD_REGS_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     s->console = graphic_console_init(DEVICE(dev), &exynos4210_fimd_ops, s);
diff --git a/hw/display/g364fb.c b/hw/display/g364fb.c
index 2a4047e1ef..79a0a5063e 100644
--- a/hw/display/g364fb.c
+++ b/hw/display/g364fb.c
@@ -486,8 +486,8 @@ static void g364fb_init(DeviceState *dev, G364State *s)
 
     s->con = graphic_console_init(dev, &g364fb_ops, s);
 
-    memory_region_init_io(&s->mem_ctrl, &g364fb_ctrl_ops, s, "ctrl", 0x180000);
-    memory_region_init_ram_ptr(&s->mem_vram, "vram",
+    memory_region_init_io(&s->mem_ctrl, NULL, &g364fb_ctrl_ops, s, "ctrl", 0x180000);
+    memory_region_init_ram_ptr(&s->mem_vram, NULL, "vram",
                                s->vram_size, s->vram);
     vmstate_register_ram(&s->mem_vram, dev);
     memory_region_set_coalescing(&s->mem_vram);
diff --git a/hw/display/jazz_led.c b/hw/display/jazz_led.c
index 52035fcacf..e6a508ef89 100644
--- a/hw/display/jazz_led.c
+++ b/hw/display/jazz_led.c
@@ -264,7 +264,7 @@ static int jazz_led_init(SysBusDevice *dev)
 {
     LedState *s = FROM_SYSBUS(LedState, dev);
 
-    memory_region_init_io(&s->iomem, &led_ops, s, "led", 1);
+    memory_region_init_io(&s->iomem, NULL, &led_ops, s, "led", 1);
     sysbus_init_mmio(dev, &s->iomem);
 
     s->con = graphic_console_init(DEVICE(dev), &jazz_led_ops, s);
diff --git a/hw/display/milkymist-tmu2.c b/hw/display/milkymist-tmu2.c
index b723a04cc9..31da796d48 100644
--- a/hw/display/milkymist-tmu2.c
+++ b/hw/display/milkymist-tmu2.c
@@ -447,7 +447,7 @@ static int milkymist_tmu2_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->regs_region, &tmu2_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &tmu2_mmio_ops, s,
             "milkymist-tmu2", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/display/milkymist-vgafb.c b/hw/display/milkymist-vgafb.c
index 3828296a3a..b1f9c168fa 100644
--- a/hw/display/milkymist-vgafb.c
+++ b/hw/display/milkymist-vgafb.c
@@ -279,7 +279,7 @@ static int milkymist_vgafb_init(SysBusDevice *dev)
 {
     MilkymistVgafbState *s = FROM_SYSBUS(typeof(*s), dev);
 
-    memory_region_init_io(&s->regs_region, &vgafb_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &vgafb_mmio_ops, s,
             "milkymist-vgafb", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/display/omap_dss.c b/hw/display/omap_dss.c
index ea3afcef5e..24ccbcc7a1 100644
--- a/hw/display/omap_dss.c
+++ b/hw/display/omap_dss.c
@@ -1053,15 +1053,15 @@ struct omap_dss_s *omap_dss_init(struct omap_target_agent_s *ta,
     s->drq = drq;
     omap_dss_reset(s);
 
-    memory_region_init_io(&s->iomem_diss1, &omap_diss_ops, s, "omap.diss1",
+    memory_region_init_io(&s->iomem_diss1, NULL, &omap_diss_ops, s, "omap.diss1",
                           omap_l4_region_size(ta, 0));
-    memory_region_init_io(&s->iomem_disc1, &omap_disc_ops, s, "omap.disc1",
+    memory_region_init_io(&s->iomem_disc1, NULL, &omap_disc_ops, s, "omap.disc1",
                           omap_l4_region_size(ta, 1));
-    memory_region_init_io(&s->iomem_rfbi1, &omap_rfbi_ops, s, "omap.rfbi1",
+    memory_region_init_io(&s->iomem_rfbi1, NULL, &omap_rfbi_ops, s, "omap.rfbi1",
                           omap_l4_region_size(ta, 2));
-    memory_region_init_io(&s->iomem_venc1, &omap_venc_ops, s, "omap.venc1",
+    memory_region_init_io(&s->iomem_venc1, NULL, &omap_venc_ops, s, "omap.venc1",
                           omap_l4_region_size(ta, 3));
-    memory_region_init_io(&s->iomem_im3, &omap_im3_ops, s,
+    memory_region_init_io(&s->iomem_im3, NULL, &omap_im3_ops, s,
                           "omap.im3", 0x1000);
 
     omap_l4_attach(ta, 0, &s->iomem_diss1);
diff --git a/hw/display/omap_lcdc.c b/hw/display/omap_lcdc.c
index fb72ebee4f..c3b9b68971 100644
--- a/hw/display/omap_lcdc.c
+++ b/hw/display/omap_lcdc.c
@@ -403,7 +403,7 @@ struct omap_lcd_panel_s *omap_lcdc_init(MemoryRegion *sysmem,
     s->sysmem = sysmem;
     omap_lcdc_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_lcdc_ops, s, "omap.lcdc", 0x100);
+    memory_region_init_io(&s->iomem, NULL, &omap_lcdc_ops, s, "omap.lcdc", 0x100);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     s->con = graphic_console_init(NULL, &omap_ops, s);
diff --git a/hw/display/pl110.c b/hw/display/pl110.c
index f259955408..15c2f38baa 100644
--- a/hw/display/pl110.c
+++ b/hw/display/pl110.c
@@ -453,7 +453,7 @@ static int pl110_init(SysBusDevice *dev)
 {
     pl110_state *s = FROM_SYSBUS(pl110_state, dev);
 
-    memory_region_init_io(&s->iomem, &pl110_ops, s, "pl110", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl110_ops, s, "pl110", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     qdev_init_gpio_in(&s->busdev.qdev, pl110_mux_ctrl_set, 1);
diff --git a/hw/display/pxa2xx_lcd.c b/hw/display/pxa2xx_lcd.c
index 3b68f26782..990931ae45 100644
--- a/hw/display/pxa2xx_lcd.c
+++ b/hw/display/pxa2xx_lcd.c
@@ -1009,7 +1009,7 @@ PXA2xxLCDState *pxa2xx_lcdc_init(MemoryRegion *sysmem,
 
     pxa2xx_lcdc_orientation(s, graphic_rotate);
 
-    memory_region_init_io(&s->iomem, &pxa2xx_lcdc_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_lcdc_ops, s,
                           "pxa2xx-lcd-controller", 0x00100000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
diff --git a/hw/display/qxl.c b/hw/display/qxl.c
index 937a402b2e..bcfcce4a75 100644
--- a/hw/display/qxl.c
+++ b/hw/display/qxl.c
@@ -1981,18 +1981,18 @@ static int qxl_init_common(PCIQXLDevice *qxl)
     pci_set_byte(&config[PCI_INTERRUPT_PIN], 1);
 
     qxl->rom_size = qxl_rom_size();
-    memory_region_init_ram(&qxl->rom_bar, "qxl.vrom", qxl->rom_size);
+    memory_region_init_ram(&qxl->rom_bar, NULL, "qxl.vrom", qxl->rom_size);
     vmstate_register_ram(&qxl->rom_bar, &qxl->pci.qdev);
     init_qxl_rom(qxl);
     init_qxl_ram(qxl);
 
     qxl->guest_surfaces.cmds = g_new0(QXLPHYSICAL, qxl->ssd.num_surfaces);
-    memory_region_init_ram(&qxl->vram_bar, "qxl.vram", qxl->vram_size);
+    memory_region_init_ram(&qxl->vram_bar, NULL, "qxl.vram", qxl->vram_size);
     vmstate_register_ram(&qxl->vram_bar, &qxl->pci.qdev);
-    memory_region_init_alias(&qxl->vram32_bar, "qxl.vram32", &qxl->vram_bar,
+    memory_region_init_alias(&qxl->vram32_bar, NULL, "qxl.vram32", &qxl->vram_bar,
                              0, qxl->vram32_size);
 
-    memory_region_init_io(&qxl->io_bar, &qxl_io_ops, qxl,
+    memory_region_init_io(&qxl->io_bar, NULL, &qxl_io_ops, qxl,
                           "qxl-ioports", io_size);
     if (qxl->id == 0) {
         vga_dirty_log_start(&qxl->vga);
@@ -2093,7 +2093,7 @@ static int qxl_init_secondary(PCIDevice *dev)
 
     qxl->id = device_id++;
     qxl_init_ramsize(qxl);
-    memory_region_init_ram(&qxl->vga.vram, "qxl.vgavram", qxl->vga.vram_size);
+    memory_region_init_ram(&qxl->vga.vram, NULL, "qxl.vgavram", qxl->vga.vram_size);
     vmstate_register_ram(&qxl->vga.vram, &qxl->pci.qdev);
     qxl->vga.vram_ptr = memory_region_get_ram_ptr(&qxl->vga.vram);
     qxl->vga.con = graphic_console_init(DEVICE(dev), &qxl_ops, qxl);
diff --git a/hw/display/sm501.c b/hw/display/sm501.c
index f72e4882a7..c75d6ac63c 100644
--- a/hw/display/sm501.c
+++ b/hw/display/sm501.c
@@ -1408,23 +1408,23 @@ void sm501_init(MemoryRegion *address_space_mem, uint32_t base,
     s->dc_crt_control = 0x00010000;
 
     /* allocate local memory */
-    memory_region_init_ram(&s->local_mem_region, "sm501.local",
+    memory_region_init_ram(&s->local_mem_region, NULL, "sm501.local",
                            local_mem_bytes);
     vmstate_register_ram_global(&s->local_mem_region);
     s->local_mem = memory_region_get_ram_ptr(&s->local_mem_region);
     memory_region_add_subregion(address_space_mem, base, &s->local_mem_region);
 
     /* map mmio */
-    memory_region_init_io(sm501_system_config, &sm501_system_config_ops, s,
+    memory_region_init_io(sm501_system_config, NULL, &sm501_system_config_ops, s,
                           "sm501-system-config", 0x6c);
     memory_region_add_subregion(address_space_mem, base + MMIO_BASE_OFFSET,
                                 sm501_system_config);
-    memory_region_init_io(sm501_disp_ctrl, &sm501_disp_ctrl_ops, s,
+    memory_region_init_io(sm501_disp_ctrl, NULL, &sm501_disp_ctrl_ops, s,
                           "sm501-disp-ctrl", 0x1000);
     memory_region_add_subregion(address_space_mem,
                                 base + MMIO_BASE_OFFSET + SM501_DC,
                                 sm501_disp_ctrl);
-    memory_region_init_io(sm501_2d_engine, &sm501_2d_engine_ops, s,
+    memory_region_init_io(sm501_2d_engine, NULL, &sm501_2d_engine_ops, s,
                           "sm501-2d-engine", 0x54);
     memory_region_add_subregion(address_space_mem,
                                 base + MMIO_BASE_OFFSET + SM501_2D_ENGINE,
diff --git a/hw/display/tc6393xb.c b/hw/display/tc6393xb.c
index 0cb87bc063..3dd9b98eca 100644
--- a/hw/display/tc6393xb.c
+++ b/hw/display/tc6393xb.c
@@ -578,10 +578,10 @@ TC6393xbState *tc6393xb_init(MemoryRegion *sysmem, uint32_t base, qemu_irq irq)
     nand = drive_get(IF_MTD, 0, 0);
     s->flash = nand_init(nand ? nand->bdrv : NULL, NAND_MFR_TOSHIBA, 0x76);
 
-    memory_region_init_io(&s->iomem, &tc6393xb_ops, s, "tc6393xb", 0x10000);
+    memory_region_init_io(&s->iomem, NULL, &tc6393xb_ops, s, "tc6393xb", 0x10000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
-    memory_region_init_ram(&s->vram, "tc6393xb.vram", 0x100000);
+    memory_region_init_ram(&s->vram, NULL, "tc6393xb.vram", 0x100000);
     vmstate_register_ram_global(&s->vram);
     s->vram_ptr = memory_region_get_ram_ptr(&s->vram);
     memory_region_add_subregion(sysmem, base + 0x100000, &s->vram);
diff --git a/hw/display/tcx.c b/hw/display/tcx.c
index 995641c745..24b5478f1b 100644
--- a/hw/display/tcx.c
+++ b/hw/display/tcx.c
@@ -528,7 +528,7 @@ static int tcx_init1(SysBusDevice *dev)
     int size;
     uint8_t *vram_base;
 
-    memory_region_init_ram(&s->vram_mem, "tcx.vram",
+    memory_region_init_ram(&s->vram_mem, NULL, "tcx.vram",
                            s->vram_size * (1 + 4 + 4));
     vmstate_register_ram_global(&s->vram_mem);
     vram_base = memory_region_get_ram_ptr(&s->vram_mem);
@@ -536,21 +536,21 @@ static int tcx_init1(SysBusDevice *dev)
     /* 8-bit plane */
     s->vram = vram_base;
     size = s->vram_size;
-    memory_region_init_alias(&s->vram_8bit, "tcx.vram.8bit",
+    memory_region_init_alias(&s->vram_8bit, NULL, "tcx.vram.8bit",
                              &s->vram_mem, vram_offset, size);
     sysbus_init_mmio(dev, &s->vram_8bit);
     vram_offset += size;
     vram_base += size;
 
     /* DAC */
-    memory_region_init_io(&s->dac, &tcx_dac_ops, s, "tcx.dac", TCX_DAC_NREGS);
+    memory_region_init_io(&s->dac, NULL, &tcx_dac_ops, s, "tcx.dac", TCX_DAC_NREGS);
     sysbus_init_mmio(dev, &s->dac);
 
     /* TEC (dummy) */
-    memory_region_init_io(&s->tec, &dummy_ops, s, "tcx.tec", TCX_TEC_NREGS);
+    memory_region_init_io(&s->tec, NULL, &dummy_ops, s, "tcx.tec", TCX_TEC_NREGS);
     sysbus_init_mmio(dev, &s->tec);
     /* THC: NetBSD writes here even with 8-bit display: dummy */
-    memory_region_init_io(&s->thc24, &dummy_ops, s, "tcx.thc24",
+    memory_region_init_io(&s->thc24, NULL, &dummy_ops, s, "tcx.thc24",
                           TCX_THC_NREGS_24);
     sysbus_init_mmio(dev, &s->thc24);
 
@@ -559,7 +559,7 @@ static int tcx_init1(SysBusDevice *dev)
         size = s->vram_size * 4;
         s->vram24 = (uint32_t *)vram_base;
         s->vram24_offset = vram_offset;
-        memory_region_init_alias(&s->vram_24bit, "tcx.vram.24bit",
+        memory_region_init_alias(&s->vram_24bit, NULL, "tcx.vram.24bit",
                                  &s->vram_mem, vram_offset, size);
         sysbus_init_mmio(dev, &s->vram_24bit);
         vram_offset += size;
@@ -569,14 +569,14 @@ static int tcx_init1(SysBusDevice *dev)
         size = s->vram_size * 4;
         s->cplane = (uint32_t *)vram_base;
         s->cplane_offset = vram_offset;
-        memory_region_init_alias(&s->vram_cplane, "tcx.vram.cplane",
+        memory_region_init_alias(&s->vram_cplane, NULL, "tcx.vram.cplane",
                                  &s->vram_mem, vram_offset, size);
         sysbus_init_mmio(dev, &s->vram_cplane);
 
         s->con = graphic_console_init(DEVICE(dev), &tcx24_ops, s);
     } else {
         /* THC 8 bit (dummy) */
-        memory_region_init_io(&s->thc8, &dummy_ops, s, "tcx.thc8",
+        memory_region_init_io(&s->thc8, NULL, &dummy_ops, s, "tcx.thc8",
                               TCX_THC_NREGS_8);
         sysbus_init_mmio(dev, &s->thc8);
 
diff --git a/hw/display/vga-isa-mm.c b/hw/display/vga-isa-mm.c
index ceeb92f8df..95707a814e 100644
--- a/hw/display/vga-isa-mm.c
+++ b/hw/display/vga-isa-mm.c
@@ -105,13 +105,13 @@ static void vga_mm_init(ISAVGAMMState *s, hwaddr vram_base,
 
     s->it_shift = it_shift;
     s_ioport_ctrl = g_malloc(sizeof(*s_ioport_ctrl));
-    memory_region_init_io(s_ioport_ctrl, &vga_mm_ctrl_ops, s,
+    memory_region_init_io(s_ioport_ctrl, NULL, &vga_mm_ctrl_ops, s,
                           "vga-mm-ctrl", 0x100000);
     memory_region_set_flush_coalesced(s_ioport_ctrl);
 
     vga_io_memory = g_malloc(sizeof(*vga_io_memory));
     /* XXX: endianness? */
-    memory_region_init_io(vga_io_memory, &vga_mem_ops, &s->vga,
+    memory_region_init_io(vga_io_memory, NULL, &vga_mem_ops, &s->vga,
                           "vga-mem", 0x20000);
 
     vmstate_register(NULL, 0, &vmstate_vga_common, s);
diff --git a/hw/display/vga-pci.c b/hw/display/vga-pci.c
index cea8db7f15..23d5b5654a 100644
--- a/hw/display/vga-pci.c
+++ b/hw/display/vga-pci.c
@@ -157,10 +157,10 @@ static int pci_std_vga_initfn(PCIDevice *dev)
 
     /* mmio bar for vga register access */
     if (d->flags & (1 << PCI_VGA_FLAG_ENABLE_MMIO)) {
-        memory_region_init(&d->mmio, "vga.mmio", 4096);
-        memory_region_init_io(&d->ioport, &pci_vga_ioport_ops, d,
+        memory_region_init(&d->mmio, NULL, "vga.mmio", 4096);
+        memory_region_init_io(&d->ioport, NULL, &pci_vga_ioport_ops, d,
                               "vga ioports remapped", PCI_VGA_IOPORT_SIZE);
-        memory_region_init_io(&d->bochs, &pci_vga_bochs_ops, d,
+        memory_region_init_io(&d->bochs, NULL, &pci_vga_bochs_ops, d,
                               "bochs dispi interface", PCI_VGA_BOCHS_SIZE);
 
         memory_region_add_subregion(&d->mmio, PCI_VGA_IOPORT_OFFSET,
diff --git a/hw/display/vga.c b/hw/display/vga.c
index 21a108d8c0..21e37633f3 100644
--- a/hw/display/vga.c
+++ b/hw/display/vga.c
@@ -198,7 +198,7 @@ static void vga_update_memory_access(VGACommonState *s)
         }
         base += isa_mem_base;
         region = g_malloc(sizeof(*region));
-        memory_region_init_alias(region, "vga.chain4", &s->vram, offset, size);
+        memory_region_init_alias(region, NULL, "vga.chain4", &s->vram, offset, size);
         memory_region_add_subregion_overlap(s->legacy_address_space, base,
                                             region, 2);
         s->chain4_alias = region;
@@ -2292,7 +2292,7 @@ void vga_common_init(VGACommonState *s)
     s->vram_size_mb = s->vram_size >> 20;
 
     s->is_vbe_vmstate = 1;
-    memory_region_init_ram(&s->vram, "vga.vram", s->vram_size);
+    memory_region_init_ram(&s->vram, NULL, "vga.vram", s->vram_size);
     vmstate_register_ram_global(&s->vram);
     xen_register_framebuffer(&s->vram);
     s->vram_ptr = memory_region_get_ram_ptr(&s->vram);
@@ -2343,7 +2343,7 @@ MemoryRegion *vga_init_io(VGACommonState *s,
     *vbe_ports = vbe_portio_list;
 
     vga_mem = g_malloc(sizeof(*vga_mem));
-    memory_region_init_io(vga_mem, &vga_mem_ops, s,
+    memory_region_init_io(vga_mem, NULL, &vga_mem_ops, s,
                           "vga-lowmem", 0x20000);
     memory_region_set_flush_coalesced(vga_mem);
 
@@ -2385,7 +2385,7 @@ void vga_init_vbe(VGACommonState *s, MemoryRegion *system_memory)
     /* With pc-0.12 and below we map both the PCI BAR and the fixed VBE region,
      * so use an alias to avoid double-mapping the same region.
      */
-    memory_region_init_alias(&s->vram_vbe, "vram.vbe",
+    memory_region_init_alias(&s->vram_vbe, NULL, "vram.vbe",
                              &s->vram, 0, memory_region_size(&s->vram));
     /* XXX: use optimized standard vga accesses */
     memory_region_add_subregion(system_memory,
diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c
index ec41681600..05be1fa614 100644
--- a/hw/display/vmware_vga.c
+++ b/hw/display/vmware_vga.c
@@ -1194,7 +1194,7 @@ static void vmsvga_init(DeviceState *dev, struct vmsvga_state_s *s,
     s->vga.con = graphic_console_init(dev, &vmsvga_ops, s);
 
     s->fifo_size = SVGA_FIFO_SIZE;
-    memory_region_init_ram(&s->fifo_ram, "vmsvga.fifo", s->fifo_size);
+    memory_region_init_ram(&s->fifo_ram, NULL, "vmsvga.fifo", s->fifo_size);
     vmstate_register_ram_global(&s->fifo_ram);
     s->fifo_ptr = memory_region_get_ram_ptr(&s->fifo_ram);
 
@@ -1257,7 +1257,7 @@ static int pci_vmsvga_initfn(PCIDevice *dev)
     s->card.config[PCI_LATENCY_TIMER] = 0x40;           /* Latency timer */
     s->card.config[PCI_INTERRUPT_LINE] = 0xff;          /* End */
 
-    memory_region_init_io(&s->io_bar, &vmsvga_io_ops, &s->chip,
+    memory_region_init_io(&s->io_bar, NULL, &vmsvga_io_ops, &s->chip,
                           "vmsvga-io", 0x10);
     memory_region_set_flush_coalesced(&s->io_bar);
     pci_register_bar(&s->card, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->io_bar);
diff --git a/hw/dma/etraxfs_dma.c b/hw/dma/etraxfs_dma.c
index 6a8c222502..3599513411 100644
--- a/hw/dma/etraxfs_dma.c
+++ b/hw/dma/etraxfs_dma.c
@@ -773,7 +773,7 @@ void *etraxfs_dmac_init(hwaddr base, int nr_channels)
 	ctrl->nr_channels = nr_channels;
 	ctrl->channels = g_malloc0(sizeof ctrl->channels[0] * nr_channels);
 
-	memory_region_init_io(&ctrl->mmio, &dma_ops, ctrl, "etraxfs-dma",
+	memory_region_init_io(&ctrl->mmio, NULL, &dma_ops, ctrl, "etraxfs-dma",
 			      nr_channels * 0x2000);
 	memory_region_add_subregion(get_system_memory(), base, &ctrl->mmio);
 
diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c
index eb60d45178..44903723d3 100644
--- a/hw/dma/i8257.c
+++ b/hw/dma/i8257.c
@@ -523,7 +523,7 @@ static void dma_init2(struct dma_cont *d, int base, int dshift,
     d->dshift = dshift;
     d->cpu_request_exit = cpu_request_exit;
 
-    memory_region_init_io(&d->channel_io, &channel_io_ops, d,
+    memory_region_init_io(&d->channel_io, NULL, &channel_io_ops, d,
                           "dma-chan", 8 << d->dshift);
     memory_region_add_subregion(isa_address_space_io(NULL),
                                 base, &d->channel_io);
@@ -535,7 +535,7 @@ static void dma_init2(struct dma_cont *d, int base, int dshift,
                                  "dma-pageh");
     }
 
-    memory_region_init_io(&d->cont_io, &cont_io_ops, d, "dma-cont",
+    memory_region_init_io(&d->cont_io, NULL, &cont_io_ops, d, "dma-cont",
                           8 << d->dshift);
     memory_region_add_subregion(isa_address_space_io(NULL),
                                 base + (8 << d->dshift), &d->cont_io);
diff --git a/hw/dma/omap_dma.c b/hw/dma/omap_dma.c
index 184fcee1a7..a81ffc4026 100644
--- a/hw/dma/omap_dma.c
+++ b/hw/dma/omap_dma.c
@@ -1663,7 +1663,7 @@ struct soc_dma_s *omap_dma_init(hwaddr base, qemu_irq *irqs,
     omap_dma_reset(s->dma);
     omap_dma_clk_update(s, 0, 1);
 
-    memory_region_init_io(&s->iomem, &omap_dma_ops, s, "omap.dma", memsize);
+    memory_region_init_io(&s->iomem, NULL, &omap_dma_ops, s, "omap.dma", memsize);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     mpu->drq = s->dma->drq;
@@ -2085,7 +2085,7 @@ struct soc_dma_s *omap_dma4_init(hwaddr base, qemu_irq *irqs,
     omap_dma_reset(s->dma);
     omap_dma_clk_update(s, 0, !!s->dma->freq);
 
-    memory_region_init_io(&s->iomem, &omap_dma4_ops, s, "omap.dma4", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &omap_dma4_ops, s, "omap.dma4", 0x1000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     mpu->drq = s->dma->drq;
diff --git a/hw/dma/pl080.c b/hw/dma/pl080.c
index 00b66b45b0..588c7b2571 100644
--- a/hw/dma/pl080.c
+++ b/hw/dma/pl080.c
@@ -359,7 +359,7 @@ static int pl08x_init(SysBusDevice *dev, int nchannels)
 {
     pl080_state *s = FROM_SYSBUS(pl080_state, dev);
 
-    memory_region_init_io(&s->iomem, &pl080_ops, s, "pl080", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl080_ops, s, "pl080", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     s->nchannels = nchannels;
diff --git a/hw/dma/pl330.c b/hw/dma/pl330.c
index 044c0876ad..b366f8acea 100644
--- a/hw/dma/pl330.c
+++ b/hw/dma/pl330.c
@@ -1528,7 +1528,7 @@ static void pl330_realize(DeviceState *dev, Error **errp)
     PL330State *s = PL330(dev);
 
     sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq_abort);
-    memory_region_init_io(&s->iomem, &pl330_ops, s, "dma", PL330_IOMEM_SIZE);
+    memory_region_init_io(&s->iomem, NULL, &pl330_ops, s, "dma", PL330_IOMEM_SIZE);
     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
 
     s->timer = qemu_new_timer_ns(vm_clock, pl330_exec_cycle_timer, s);
diff --git a/hw/dma/puv3_dma.c b/hw/dma/puv3_dma.c
index 32844b5f75..787e9a1c4d 100644
--- a/hw/dma/puv3_dma.c
+++ b/hw/dma/puv3_dma.c
@@ -80,7 +80,7 @@ static int puv3_dma_init(SysBusDevice *dev)
         s->reg_CFG[i] = 0x0;
     }
 
-    memory_region_init_io(&s->iomem, &puv3_dma_ops, s, "puv3_dma",
+    memory_region_init_io(&s->iomem, NULL, &puv3_dma_ops, s, "puv3_dma",
             PUV3_REGS_OFFSET);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/dma/pxa2xx_dma.c b/hw/dma/pxa2xx_dma.c
index b60569fd88..43e2dc3b22 100644
--- a/hw/dma/pxa2xx_dma.c
+++ b/hw/dma/pxa2xx_dma.c
@@ -465,7 +465,7 @@ static int pxa2xx_dma_init(SysBusDevice *dev)
 
     qdev_init_gpio_in(&dev->qdev, pxa2xx_dma_request, PXA2XX_DMA_NUM_REQUESTS);
 
-    memory_region_init_io(&s->iomem, &pxa2xx_dma_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_dma_ops, s,
                           "pxa2xx.dma", 0x00010000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
diff --git a/hw/dma/rc4030.c b/hw/dma/rc4030.c
index 03f92f1ab6..4ec433f957 100644
--- a/hw/dma/rc4030.c
+++ b/hw/dma/rc4030.c
@@ -814,10 +814,10 @@ void *rc4030_init(qemu_irq timer, qemu_irq jazz_bus,
     register_savevm(NULL, "rc4030", 0, 2, rc4030_save, rc4030_load, s);
     rc4030_reset(s);
 
-    memory_region_init_io(&s->iomem_chipset, &rc4030_ops, s,
+    memory_region_init_io(&s->iomem_chipset, NULL, &rc4030_ops, s,
                           "rc4030.chipset", 0x300);
     memory_region_add_subregion(sysmem, 0x80000000, &s->iomem_chipset);
-    memory_region_init_io(&s->iomem_jazzio, &jazzio_ops, s,
+    memory_region_init_io(&s->iomem_jazzio, NULL, &jazzio_ops, s,
                           "rc4030.jazzio", 0x00001000);
     memory_region_add_subregion(sysmem, 0xf0000000, &s->iomem_jazzio);
 
diff --git a/hw/dma/sparc32_dma.c b/hw/dma/sparc32_dma.c
index fd21533f15..4abb024647 100644
--- a/hw/dma/sparc32_dma.c
+++ b/hw/dma/sparc32_dma.c
@@ -274,7 +274,7 @@ static int sparc32_dma_init1(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq);
 
     reg_size = s->is_ledma ? DMA_ETH_SIZE : DMA_SIZE;
-    memory_region_init_io(&s->iomem, &dma_mem_ops, s, "dma", reg_size);
+    memory_region_init_io(&s->iomem, NULL, &dma_mem_ops, s, "dma", reg_size);
     sysbus_init_mmio(dev, &s->iomem);
 
     qdev_init_gpio_in(&dev->qdev, dma_set_irq, 1);
diff --git a/hw/dma/sun4m_iommu.c b/hw/dma/sun4m_iommu.c
index 8312bff5fe..eafb99130f 100644
--- a/hw/dma/sun4m_iommu.c
+++ b/hw/dma/sun4m_iommu.c
@@ -349,7 +349,7 @@ static int iommu_init1(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->iomem, &iommu_mem_ops, s, "iommu",
+    memory_region_init_io(&s->iomem, NULL, &iommu_mem_ops, s, "iommu",
                           IOMMU_NREGS * sizeof(uint32_t));
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
index 50054cf851..bdce6351bb 100644
--- a/hw/dma/xilinx_axidma.c
+++ b/hw/dma/xilinx_axidma.c
@@ -590,7 +590,7 @@ static void xilinx_axidma_init(Object *obj)
     sysbus_init_irq(sbd, &s->streams[0].irq);
     sysbus_init_irq(sbd, &s->streams[1].irq);
 
-    memory_region_init_io(&s->iomem, &axidma_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &axidma_ops, s,
                           "xlnx.axi-dma", R_MAX * 4 * 2);
     sysbus_init_mmio(sbd, &s->iomem);
 }
diff --git a/hw/gpio/omap_gpio.c b/hw/gpio/omap_gpio.c
index f5eeaea549..13399f9a12 100644
--- a/hw/gpio/omap_gpio.c
+++ b/hw/gpio/omap_gpio.c
@@ -677,7 +677,7 @@ static int omap_gpio_init(SysBusDevice *dev)
     qdev_init_gpio_in(&dev->qdev, omap_gpio_set, 16);
     qdev_init_gpio_out(&dev->qdev, s->omap1.handler, 16);
     sysbus_init_irq(dev, &s->omap1.irq);
-    memory_region_init_io(&s->iomem, &omap_gpio_ops, &s->omap1,
+    memory_region_init_io(&s->iomem, NULL, &omap_gpio_ops, &s->omap1,
                           "omap.gpio", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
@@ -692,7 +692,7 @@ static int omap2_gpio_init(SysBusDevice *dev)
     }
     if (s->mpu_model < omap3430) {
         s->modulecount = (s->mpu_model < omap2430) ? 4 : 5;
-        memory_region_init_io(&s->iomem, &omap2_gpif_top_ops, s,
+        memory_region_init_io(&s->iomem, NULL, &omap2_gpif_top_ops, s,
                               "omap2.gpio", 0x1000);
         sysbus_init_mmio(dev, &s->iomem);
     } else {
@@ -712,7 +712,7 @@ static int omap2_gpio_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &m->irq[0]); /* mpu irq */
         sysbus_init_irq(dev, &m->irq[1]); /* dsp irq */
         sysbus_init_irq(dev, &m->wkup);
-        memory_region_init_io(&m->iomem, &omap2_gpio_module_ops, m,
+        memory_region_init_io(&m->iomem, NULL, &omap2_gpio_module_ops, m,
                               "omap.gpio-module", 0x1000);
         sysbus_init_mmio(dev, &m->iomem);
     }
diff --git a/hw/gpio/pl061.c b/hw/gpio/pl061.c
index 74bc109488..d0dd636ffd 100644
--- a/hw/gpio/pl061.c
+++ b/hw/gpio/pl061.c
@@ -276,7 +276,7 @@ static int pl061_init(SysBusDevice *dev, const unsigned char *id)
 {
     pl061_state *s = FROM_SYSBUS(pl061_state, dev);
     s->id = id;
-    memory_region_init_io(&s->iomem, &pl061_ops, s, "pl061", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl061_ops, s, "pl061", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     qdev_init_gpio_in(&dev->qdev, pl061_set_irq, 8);
diff --git a/hw/gpio/puv3_gpio.c b/hw/gpio/puv3_gpio.c
index 5bab97e95a..333c920a7c 100644
--- a/hw/gpio/puv3_gpio.c
+++ b/hw/gpio/puv3_gpio.c
@@ -112,7 +112,7 @@ static int puv3_gpio_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq[PUV3_IRQS_GPIOLOW7]);
     sysbus_init_irq(dev, &s->irq[PUV3_IRQS_GPIOHIGH]);
 
-    memory_region_init_io(&s->iomem, &puv3_gpio_ops, s, "puv3_gpio",
+    memory_region_init_io(&s->iomem, NULL, &puv3_gpio_ops, s, "puv3_gpio",
             PUV3_REGS_OFFSET);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/gpio/zaurus.c b/hw/gpio/zaurus.c
index c6cdef3212..a0e18c3c32 100644
--- a/hw/gpio/zaurus.c
+++ b/hw/gpio/zaurus.c
@@ -169,7 +169,7 @@ static int scoop_init(SysBusDevice *dev)
     s->status = 0x02;
     qdev_init_gpio_out(&s->busdev.qdev, s->handler, 16);
     qdev_init_gpio_in(&s->busdev.qdev, scoop_gpio_set, 16);
-    memory_region_init_io(&s->iomem, &scoop_ops, s, "scoop", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &scoop_ops, s, "scoop", 0x1000);
 
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/i2c/bitbang_i2c.c b/hw/i2c/bitbang_i2c.c
index 854b8e1940..f550ba4a88 100644
--- a/hw/i2c/bitbang_i2c.c
+++ b/hw/i2c/bitbang_i2c.c
@@ -209,7 +209,7 @@ static int gpio_i2c_init(SysBusDevice *dev)
     GPIOI2CState *s = FROM_SYSBUS(GPIOI2CState, dev);
     i2c_bus *bus;
 
-    memory_region_init(&s->dummy_iomem, "gpio_i2c", 0);
+    memory_region_init(&s->dummy_iomem, NULL, "gpio_i2c", 0);
     sysbus_init_mmio(dev, &s->dummy_iomem);
 
     bus = i2c_init_bus(&dev->qdev, "i2c");
diff --git a/hw/i2c/exynos4210_i2c.c b/hw/i2c/exynos4210_i2c.c
index 196f88907d..bc6eb34374 100644
--- a/hw/i2c/exynos4210_i2c.c
+++ b/hw/i2c/exynos4210_i2c.c
@@ -301,7 +301,7 @@ static int exynos4210_i2c_realize(SysBusDevice *dev)
 {
     Exynos4210I2CState *s = EXYNOS4_I2C(dev);
 
-    memory_region_init_io(&s->iomem, &exynos4210_i2c_ops, s, TYPE_EXYNOS4_I2C,
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_i2c_ops, s, TYPE_EXYNOS4_I2C,
                           EXYNOS4_I2C_MEM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
diff --git a/hw/i2c/omap_i2c.c b/hw/i2c/omap_i2c.c
index efb2254aea..1a8b39c827 100644
--- a/hw/i2c/omap_i2c.c
+++ b/hw/i2c/omap_i2c.c
@@ -448,7 +448,7 @@ static int omap_i2c_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq);
     sysbus_init_irq(dev, &s->drq[0]);
     sysbus_init_irq(dev, &s->drq[1]);
-    memory_region_init_io(&s->iomem, &omap_i2c_ops, s, "omap.i2c",
+    memory_region_init_io(&s->iomem, NULL, &omap_i2c_ops, s, "omap.i2c",
                           (s->revision < OMAP2_INTR_REV) ? 0x800 : 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     s->bus = i2c_init_bus(&dev->qdev, NULL);
diff --git a/hw/i2c/pm_smbus.c b/hw/i2c/pm_smbus.c
index 0b5bb89976..f425ad893b 100644
--- a/hw/i2c/pm_smbus.c
+++ b/hw/i2c/pm_smbus.c
@@ -181,5 +181,5 @@ static const MemoryRegionOps pm_smbus_ops = {
 void pm_smbus_init(DeviceState *parent, PMSMBus *smb)
 {
     smb->smbus = i2c_init_bus(parent, "i2c");
-    memory_region_init_io(&smb->io, &pm_smbus_ops, smb, "pm-smbus", 64);
+    memory_region_init_io(&smb->io, NULL, &pm_smbus_ops, smb, "pm-smbus", 64);
 }
diff --git a/hw/i2c/versatile_i2c.c b/hw/i2c/versatile_i2c.c
index e09c83dda2..a239963db8 100644
--- a/hw/i2c/versatile_i2c.c
+++ b/hw/i2c/versatile_i2c.c
@@ -79,7 +79,7 @@ static int versatile_i2c_init(SysBusDevice *dev)
 
     bus = i2c_init_bus(&dev->qdev, "i2c");
     s->bitbang = bitbang_i2c_init(bus);
-    memory_region_init_io(&s->iomem, &versatile_i2c_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &versatile_i2c_ops, s,
                           "versatile_i2c", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
diff --git a/hw/i386/kvm/apic.c b/hw/i386/kvm/apic.c
index bd0bdd8590..179b806d96 100644
--- a/hw/i386/kvm/apic.c
+++ b/hw/i386/kvm/apic.c
@@ -173,7 +173,7 @@ static const MemoryRegionOps kvm_apic_io_ops = {
 
 static void kvm_apic_init(APICCommonState *s)
 {
-    memory_region_init_io(&s->io_memory, &kvm_apic_io_ops, s, "kvm-apic-msi",
+    memory_region_init_io(&s->io_memory, NULL, &kvm_apic_io_ops, s, "kvm-apic-msi",
                           APIC_SPACE_SIZE);
 
     if (kvm_has_gsi_routing()) {
diff --git a/hw/i386/kvm/i8254.c b/hw/i386/kvm/i8254.c
index 93a3669746..c1f40948f9 100644
--- a/hw/i386/kvm/i8254.c
+++ b/hw/i386/kvm/i8254.c
@@ -288,7 +288,7 @@ static void kvm_pit_realizefn(DeviceState *dev, Error **errp)
         return;
     }
 
-    memory_region_init_reservation(&pit->ioports, "kvm-pit", 4);
+    memory_region_init_reservation(&pit->ioports, NULL, "kvm-pit", 4);
 
     qdev_init_gpio_in(dev, kvm_pit_irq_control, 1);
 
diff --git a/hw/i386/kvm/i8259.c b/hw/i386/kvm/i8259.c
index 125022422a..53e3ca8c67 100644
--- a/hw/i386/kvm/i8259.c
+++ b/hw/i386/kvm/i8259.c
@@ -119,8 +119,8 @@ static void kvm_pic_realize(DeviceState *dev, Error **errp)
     PICCommonState *s = PIC_COMMON(dev);
     KVMPICClass *kpc = KVM_PIC_GET_CLASS(dev);
 
-    memory_region_init_reservation(&s->base_io, "kvm-pic", 2);
-    memory_region_init_reservation(&s->elcr_io, "kvm-elcr", 1);
+    memory_region_init_reservation(&s->base_io, NULL, "kvm-pic", 2);
+    memory_region_init_reservation(&s->elcr_io, NULL, "kvm-elcr", 1);
 
     kpc->parent_realize(dev, errp);
 }
diff --git a/hw/i386/kvm/ioapic.c b/hw/i386/kvm/ioapic.c
index abfac3da7a..688cb5cab3 100644
--- a/hw/i386/kvm/ioapic.c
+++ b/hw/i386/kvm/ioapic.c
@@ -129,7 +129,7 @@ static void kvm_ioapic_set_irq(void *opaque, int irq, int level)
 
 static void kvm_ioapic_init(IOAPICCommonState *s, int instance_no)
 {
-    memory_region_init_reservation(&s->io_memory, "kvm-ioapic", 0x1000);
+    memory_region_init_reservation(&s->io_memory, NULL, "kvm-ioapic", 0x1000);
 
     qdev_init_gpio_in(&s->busdev.qdev, kvm_ioapic_set_irq, IOAPIC_NUM_PINS);
 }
diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
index 1fb7ad44ab..f1a55544f2 100644
--- a/hw/i386/kvm/pci-assign.c
+++ b/hw/i386/kvm/pci-assign.c
@@ -298,7 +298,7 @@ static void assigned_dev_iomem_setup(PCIDevice *pci_dev, int region_num,
     PCIRegion *real_region = &r_dev->real_device.regions[region_num];
 
     if (e_size > 0) {
-        memory_region_init(&region->container, "assigned-dev-container",
+        memory_region_init(&region->container, NULL, "assigned-dev-container",
                            e_size);
         memory_region_add_subregion(&region->container, 0, &region->real_iomem);
 
@@ -329,8 +329,8 @@ static void assigned_dev_ioport_setup(PCIDevice *pci_dev, int region_num,
     AssignedDevRegion *region = &r_dev->v_addrs[region_num];
 
     region->e_size = size;
-    memory_region_init(&region->container, "assigned-dev-container", size);
-    memory_region_init_io(&region->real_iomem, &assigned_dev_ioport_ops,
+    memory_region_init(&region->container, NULL, "assigned-dev-container", size);
+    memory_region_init_io(&region->real_iomem, NULL, &assigned_dev_ioport_ops,
                           r_dev->v_addrs + region_num,
                           "assigned-dev-iomem", size);
     memory_region_add_subregion(&region->container, 0, &region->real_iomem);
@@ -478,7 +478,7 @@ static int assigned_dev_register_regions(PCIRegion *io_regions,
                              "4K.  You might experience some performance hit "
                              "due to that.",
                              i, cur_region->base_addr, cur_region->size);
-                memory_region_init_io(&pci_dev->v_addrs[i].real_iomem,
+                memory_region_init_io(&pci_dev->v_addrs[i].real_iomem, NULL,
                                       &slow_bar_ops, &pci_dev->v_addrs[i],
                                       "assigned-dev-slow-bar",
                                       cur_region->size);
@@ -487,7 +487,7 @@ static int assigned_dev_register_regions(PCIRegion *io_regions,
                 char name[32];
                 snprintf(name, sizeof(name), "%s.bar%d",
                          object_get_typename(OBJECT(pci_dev)), i);
-                memory_region_init_ram_ptr(&pci_dev->v_addrs[i].real_iomem,
+                memory_region_init_ram_ptr(&pci_dev->v_addrs[i].real_iomem, NULL,
                                            name, cur_region->size,
                                            virtbase);
                 vmstate_register_ram(&pci_dev->v_addrs[i].real_iomem,
@@ -1650,7 +1650,7 @@ static int assigned_dev_register_msix_mmio(AssignedDevice *dev)
 
     assigned_dev_msix_reset(dev);
 
-    memory_region_init_io(&dev->mmio, &assigned_dev_msix_mmio_ops, dev,
+    memory_region_init_io(&dev->mmio, NULL, &assigned_dev_msix_mmio_ops, dev,
                           "assigned-dev-msix", MSIX_PAGE_SIZE);
     return 0;
 }
@@ -1916,7 +1916,7 @@ static void assigned_dev_load_option_rom(AssignedDevice *dev)
 
     snprintf(name, sizeof(name), "%s.rom",
             object_get_typename(OBJECT(dev)));
-    memory_region_init_ram(&dev->dev.rom, name, st.st_size);
+    memory_region_init_ram(&dev->dev.rom, NULL, name, st.st_size);
     vmstate_register_ram(&dev->dev.rom, &dev->dev.qdev);
     ptr = memory_region_get_ram_ptr(&dev->dev.rom);
     memset(ptr, 0xff, st.st_size);
diff --git a/hw/i386/kvmvapic.c b/hw/i386/kvmvapic.c
index f93629f9d4..08da69e4d1 100644
--- a/hw/i386/kvmvapic.c
+++ b/hw/i386/kvmvapic.c
@@ -601,7 +601,7 @@ static void vapic_map_rom_writable(VAPICROMState *s)
     rom_paddr &= TARGET_PAGE_MASK;
     rom_size = TARGET_PAGE_ALIGN(rom_size);
 
-    memory_region_init_alias(&s->rom, "kvmvapic-rom", section.mr, rom_paddr,
+    memory_region_init_alias(&s->rom, NULL, "kvmvapic-rom", section.mr, rom_paddr,
                              rom_size);
     memory_region_add_subregion_overlap(as, rom_paddr, &s->rom, 1000);
     s->rom_mapped_writable = true;
@@ -702,7 +702,7 @@ static int vapic_init(SysBusDevice *dev)
 {
     VAPICROMState *s = VAPIC(dev);
 
-    memory_region_init_io(&s->io, &vapic_ops, s, "kvmvapic", 2);
+    memory_region_init_io(&s->io, NULL, &vapic_ops, s, "kvmvapic", 2);
     sysbus_add_io(dev, VAPIC_IO_PORT, &s->io);
     sysbus_init_ioports(dev, VAPIC_IO_PORT, 2);
 
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 78f92e29a7..4345187d1a 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -525,7 +525,7 @@ static void port92_initfn(Object *obj)
 {
     Port92State *s = PORT92(obj);
 
-    memory_region_init_io(&s->io, &port92_ops, s, "port92", 1);
+    memory_region_init_io(&s->io, NULL, &port92_ops, s, "port92", 1);
 
     s->outport = 0;
 }
@@ -1044,17 +1044,17 @@ FWCfgState *pc_memory_init(MemoryRegion *system_memory,
      * with older qemus that used qemu_ram_alloc().
      */
     ram = g_malloc(sizeof(*ram));
-    memory_region_init_ram(ram, "pc.ram",
+    memory_region_init_ram(ram, NULL, "pc.ram",
                            below_4g_mem_size + above_4g_mem_size);
     vmstate_register_ram_global(ram);
     *ram_memory = ram;
     ram_below_4g = g_malloc(sizeof(*ram_below_4g));
-    memory_region_init_alias(ram_below_4g, "ram-below-4g", ram,
+    memory_region_init_alias(ram_below_4g, NULL, "ram-below-4g", ram,
                              0, below_4g_mem_size);
     memory_region_add_subregion(system_memory, 0, ram_below_4g);
     if (above_4g_mem_size > 0) {
         ram_above_4g = g_malloc(sizeof(*ram_above_4g));
-        memory_region_init_alias(ram_above_4g, "ram-above-4g", ram,
+        memory_region_init_alias(ram_above_4g, NULL, "ram-above-4g", ram,
                                  below_4g_mem_size, above_4g_mem_size);
         memory_region_add_subregion(system_memory, 0x100000000ULL,
                                     ram_above_4g);
@@ -1065,7 +1065,7 @@ FWCfgState *pc_memory_init(MemoryRegion *system_memory,
     pc_system_firmware_init(rom_memory);
 
     option_rom_mr = g_malloc(sizeof(*option_rom_mr));
-    memory_region_init_ram(option_rom_mr, "pc.rom", PC_ROM_SIZE);
+    memory_region_init_ram(option_rom_mr, NULL, "pc.rom", PC_ROM_SIZE);
     vmstate_register_ram_global(option_rom_mr);
     memory_region_add_subregion_overlap(rom_memory,
                                         PC_ROM_MIN_VGA,
@@ -1150,10 +1150,10 @@ void pc_basic_device_init(ISABus *isa_bus, qemu_irq *gsi,
     MemoryRegion *ioport80_io = g_new(MemoryRegion, 1);
     MemoryRegion *ioportF0_io = g_new(MemoryRegion, 1);
 
-    memory_region_init_io(ioport80_io, &ioport80_io_ops, NULL, "ioport80", 1);
+    memory_region_init_io(ioport80_io, NULL, &ioport80_io_ops, NULL, "ioport80", 1);
     memory_region_add_subregion(isa_bus->address_space_io, 0x80, ioport80_io);
 
-    memory_region_init_io(ioportF0_io, &ioportF0_io_ops, NULL, "ioportF0", 1);
+    memory_region_init_io(ioportF0_io, NULL, &ioportF0_io_ops, NULL, "ioportF0", 1);
     memory_region_add_subregion(isa_bus->address_space_io, 0xf0, ioportF0_io);
 
     /*
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index fa59a0cb26..faf947e661 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -117,7 +117,7 @@ static void pc_init1(MemoryRegion *system_memory,
 
     if (pci_enabled) {
         pci_memory = g_new(MemoryRegion, 1);
-        memory_region_init(pci_memory, "pci", INT64_MAX);
+        memory_region_init(pci_memory, NULL, "pci", INT64_MAX);
         rom_memory = pci_memory;
     } else {
         pci_memory = NULL;
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index bb0ce6ae6b..e4cde042ce 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -98,7 +98,7 @@ static void pc_q35_init(QEMUMachineInitArgs *args)
     /* pci enabled */
     if (pci_enabled) {
         pci_memory = g_new(MemoryRegion, 1);
-        memory_region_init(pci_memory, "pci", INT64_MAX);
+        memory_region_init(pci_memory, NULL, "pci", INT64_MAX);
         rom_memory = pci_memory;
     } else {
         pci_memory = NULL;
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index 931dacd260..e7734f3b13 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -1158,8 +1158,8 @@ void ahci_init(AHCIState *s, DeviceState *qdev, AddressSpace *as, int ports)
     s->dev = g_malloc0(sizeof(AHCIDevice) * ports);
     ahci_reg_init(s);
     /* XXX BAR size should be 1k, but that breaks, so bump it to 4k for now */
-    memory_region_init_io(&s->mem, &ahci_mem_ops, s, "ahci", AHCI_MEM_BAR_SIZE);
-    memory_region_init_io(&s->idp, &ahci_idp_ops, s, "ahci-idp", 32);
+    memory_region_init_io(&s->mem, NULL, &ahci_mem_ops, s, "ahci", AHCI_MEM_BAR_SIZE);
+    memory_region_init_io(&s->idp, NULL, &ahci_idp_ops, s, "ahci-idp", 32);
 
     irqs = qemu_allocate_irqs(ahci_irq_set, s, s->ports);
 
diff --git a/hw/ide/cmd646.c b/hw/ide/cmd646.c
index 99167011dd..a695dfb837 100644
--- a/hw/ide/cmd646.c
+++ b/hw/ide/cmd646.c
@@ -117,8 +117,8 @@ static void setup_cmd646_bar(PCIIDEState *d, int bus_num)
 
     bar->bus = bus;
     bar->pci_dev = d;
-    memory_region_init_io(&bar->cmd, &cmd646_cmd_ops, bar, "cmd646-cmd", 4);
-    memory_region_init_io(&bar->data, &cmd646_data_ops, bar, "cmd646-data", 8);
+    memory_region_init_io(&bar->cmd, NULL, &cmd646_cmd_ops, bar, "cmd646-cmd", 4);
+    memory_region_init_io(&bar->data, NULL, &cmd646_data_ops, bar, "cmd646-data", 8);
 }
 
 static uint64_t bmdma_read(void *opaque, hwaddr addr,
@@ -203,13 +203,13 @@ static void bmdma_setup_bar(PCIIDEState *d)
     BMDMAState *bm;
     int i;
 
-    memory_region_init(&d->bmdma_bar, "cmd646-bmdma", 16);
+    memory_region_init(&d->bmdma_bar, NULL, "cmd646-bmdma", 16);
     for(i = 0;i < 2; i++) {
         bm = &d->bmdma[i];
-        memory_region_init_io(&bm->extra_io, &cmd646_bmdma_ops, bm,
+        memory_region_init_io(&bm->extra_io, NULL, &cmd646_bmdma_ops, bm,
                               "cmd646-bmdma-bus", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8, &bm->extra_io);
-        memory_region_init_io(&bm->addr_ioport, &bmdma_addr_ioport_ops, bm,
+        memory_region_init_io(&bm->addr_ioport, NULL, &bmdma_addr_ioport_ops, bm,
                               "cmd646-bmdma-ioport", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8 + 4, &bm->addr_ioport);
     }
diff --git a/hw/ide/macio.c b/hw/ide/macio.c
index 84288ae2ad..0c14009116 100644
--- a/hw/ide/macio.c
+++ b/hw/ide/macio.c
@@ -335,7 +335,7 @@ static void macio_ide_initfn(Object *obj)
     MACIOIDEState *s = MACIO_IDE(obj);
 
     ide_bus_new(&s->bus, DEVICE(obj), 0, 2);
-    memory_region_init_io(&s->mem, &pmac_ide_ops, s, "pmac-ide", 0x1000);
+    memory_region_init_io(&s->mem, NULL, &pmac_ide_ops, s, "pmac-ide", 0x1000);
     sysbus_init_mmio(d, &s->mem);
     sysbus_init_irq(d, &s->irq);
     sysbus_init_irq(d, &s->dma_irq);
diff --git a/hw/ide/mmio.c b/hw/ide/mmio.c
index e80e7e5af8..8ae57d64a1 100644
--- a/hw/ide/mmio.c
+++ b/hw/ide/mmio.c
@@ -124,9 +124,9 @@ static void mmio_ide_realizefn(DeviceState *dev, Error **errp)
 
     ide_init2(&s->bus, s->irq);
 
-    memory_region_init_io(&s->iomem1, &mmio_ide_ops, s,
+    memory_region_init_io(&s->iomem1, NULL, &mmio_ide_ops, s,
                           "ide-mmio.1", 16 << s->shift);
-    memory_region_init_io(&s->iomem2, &mmio_ide_cs_ops, s,
+    memory_region_init_io(&s->iomem2, NULL, &mmio_ide_cs_ops, s,
                           "ide-mmio.2", 2 << s->shift);
     sysbus_init_mmio(d, &s->iomem1);
     sysbus_init_mmio(d, &s->iomem2);
diff --git a/hw/ide/piix.c b/hw/ide/piix.c
index bf2856fb69..af445dbc7c 100644
--- a/hw/ide/piix.c
+++ b/hw/ide/piix.c
@@ -90,14 +90,14 @@ static void bmdma_setup_bar(PCIIDEState *d)
 {
     int i;
 
-    memory_region_init(&d->bmdma_bar, "piix-bmdma-container", 16);
+    memory_region_init(&d->bmdma_bar, NULL, "piix-bmdma-container", 16);
     for(i = 0;i < 2; i++) {
         BMDMAState *bm = &d->bmdma[i];
 
-        memory_region_init_io(&bm->extra_io, &piix_bmdma_ops, bm,
+        memory_region_init_io(&bm->extra_io, NULL, &piix_bmdma_ops, bm,
                               "piix-bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8, &bm->extra_io);
-        memory_region_init_io(&bm->addr_ioport, &bmdma_addr_ioport_ops, bm,
+        memory_region_init_io(&bm->addr_ioport, NULL, &bmdma_addr_ioport_ops, bm,
                               "bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8 + 4, &bm->addr_ioport);
     }
diff --git a/hw/ide/via.c b/hw/ide/via.c
index 5fe053cf97..1691717ae4 100644
--- a/hw/ide/via.c
+++ b/hw/ide/via.c
@@ -92,14 +92,14 @@ static void bmdma_setup_bar(PCIIDEState *d)
 {
     int i;
 
-    memory_region_init(&d->bmdma_bar, "via-bmdma-container", 16);
+    memory_region_init(&d->bmdma_bar, NULL, "via-bmdma-container", 16);
     for(i = 0;i < 2; i++) {
         BMDMAState *bm = &d->bmdma[i];
 
-        memory_region_init_io(&bm->extra_io, &via_bmdma_ops, bm,
+        memory_region_init_io(&bm->extra_io, NULL, &via_bmdma_ops, bm,
                               "via-bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8, &bm->extra_io);
-        memory_region_init_io(&bm->addr_ioport, &bmdma_addr_ioport_ops, bm,
+        memory_region_init_io(&bm->addr_ioport, NULL, &bmdma_addr_ioport_ops, bm,
                               "bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8 + 4, &bm->addr_ioport);
     }
diff --git a/hw/input/milkymist-softusb.c b/hw/input/milkymist-softusb.c
index 3edab4ff0b..69e64852f8 100644
--- a/hw/input/milkymist-softusb.c
+++ b/hw/input/milkymist-softusb.c
@@ -265,17 +265,17 @@ static int milkymist_softusb_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->regs_region, &softusb_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &softusb_mmio_ops, s,
                           "milkymist-softusb", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
     /* register pmem and dmem */
-    memory_region_init_ram(&s->pmem, "milkymist-softusb.pmem",
+    memory_region_init_ram(&s->pmem, NULL, "milkymist-softusb.pmem",
                            s->pmem_size);
     vmstate_register_ram_global(&s->pmem);
     s->pmem_ptr = memory_region_get_ram_ptr(&s->pmem);
     sysbus_init_mmio(dev, &s->pmem);
-    memory_region_init_ram(&s->dmem, "milkymist-softusb.dmem",
+    memory_region_init_ram(&s->dmem, NULL, "milkymist-softusb.dmem",
                            s->dmem_size);
     vmstate_register_ram_global(&s->dmem);
     s->dmem_ptr = memory_region_get_ram_ptr(&s->dmem);
diff --git a/hw/input/pckbd.c b/hw/input/pckbd.c
index fff0a4d1f8..8d1d6a75f0 100644
--- a/hw/input/pckbd.c
+++ b/hw/input/pckbd.c
@@ -424,7 +424,7 @@ void i8042_mm_init(qemu_irq kbd_irq, qemu_irq mouse_irq,
 
     vmstate_register(NULL, 0, &vmstate_kbd, s);
 
-    memory_region_init_io(region, &i8042_mmio_ops, s, "i8042", size);
+    memory_region_init_io(region, NULL, &i8042_mmio_ops, s, "i8042", size);
 
     s->kbd = ps2_kbd_init(kbd_update_kbd_irq, s);
     s->mouse = ps2_mouse_init(kbd_update_aux_irq, s);
@@ -494,8 +494,8 @@ static void i8042_initfn(Object *obj)
     ISAKBDState *isa_s = I8042(obj);
     KBDState *s = &isa_s->kbd;
 
-    memory_region_init_io(isa_s->io + 0, &i8042_data_ops, s, "i8042-data", 1);
-    memory_region_init_io(isa_s->io + 1, &i8042_cmd_ops, s, "i8042-cmd", 1);
+    memory_region_init_io(isa_s->io + 0, NULL, &i8042_data_ops, s, "i8042-data", 1);
+    memory_region_init_io(isa_s->io + 1, NULL, &i8042_cmd_ops, s, "i8042-cmd", 1);
 }
 
 static void i8042_realizefn(DeviceState *dev, Error **errp)
diff --git a/hw/input/pl050.c b/hw/input/pl050.c
index 7dd8a59dd4..871ffbaeca 100644
--- a/hw/input/pl050.c
+++ b/hw/input/pl050.c
@@ -137,7 +137,7 @@ static int pl050_init(SysBusDevice *dev, int is_mouse)
 {
     pl050_state *s = FROM_SYSBUS(pl050_state, dev);
 
-    memory_region_init_io(&s->iomem, &pl050_ops, s, "pl050", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl050_ops, s, "pl050", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     s->is_mouse = is_mouse;
diff --git a/hw/input/pxa2xx_keypad.c b/hw/input/pxa2xx_keypad.c
index 1fd5f2076a..846d1370de 100644
--- a/hw/input/pxa2xx_keypad.c
+++ b/hw/input/pxa2xx_keypad.c
@@ -313,7 +313,7 @@ PXA2xxKeyPadState *pxa27x_keypad_init(MemoryRegion *sysmem,
     s = (PXA2xxKeyPadState *) g_malloc0(sizeof(PXA2xxKeyPadState));
     s->irq = irq;
 
-    memory_region_init_io(&s->iomem, &pxa2xx_keypad_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_keypad_ops, s,
                           "pxa2xx-keypad", 0x00100000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
diff --git a/hw/intc/apic.c b/hw/intc/apic.c
index 46cb0975d9..d15c8be450 100644
--- a/hw/intc/apic.c
+++ b/hw/intc/apic.c
@@ -873,7 +873,7 @@ static const MemoryRegionOps apic_io_ops = {
 
 static void apic_init(APICCommonState *s)
 {
-    memory_region_init_io(&s->io_memory, &apic_io_ops, s, "apic-msi",
+    memory_region_init_io(&s->io_memory, NULL, &apic_io_ops, s, "apic-msi",
                           APIC_SPACE_SIZE);
 
     s->timer = qemu_new_timer_ns(vm_clock, apic_timer, s);
diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
index bae65721fd..a5ff762eb6 100644
--- a/hw/intc/arm_gic.c
+++ b/hw/intc/arm_gic.c
@@ -656,7 +656,7 @@ void gic_init_irqs_and_distributor(GICState *s, int num_irq)
     for (i = 0; i < NUM_CPU(s); i++) {
         sysbus_init_irq(&s->busdev, &s->parent_irq[i]);
     }
-    memory_region_init_io(&s->iomem, &gic_dist_ops, s, "gic_dist", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &gic_dist_ops, s, "gic_dist", 0x1000);
 }
 
 static void arm_gic_realize(DeviceState *dev, Error **errp)
@@ -682,11 +682,11 @@ static void arm_gic_realize(DeviceState *dev, Error **errp)
      * GIC v2 defines a larger memory region (0x1000) so this will need
      * to be extended when we implement A15.
      */
-    memory_region_init_io(&s->cpuiomem[0], &gic_thiscpu_ops, s,
+    memory_region_init_io(&s->cpuiomem[0], NULL, &gic_thiscpu_ops, s,
                           "gic_cpu", 0x100);
     for (i = 0; i < NUM_CPU(s); i++) {
         s->backref[i] = s;
-        memory_region_init_io(&s->cpuiomem[i+1], &gic_cpu_ops, &s->backref[i],
+        memory_region_init_io(&s->cpuiomem[i+1], NULL, &gic_cpu_ops, &s->backref[i],
                               "gic_cpu", 0x100);
     }
     /* Distributor */
diff --git a/hw/intc/arm_gic_kvm.c b/hw/intc/arm_gic_kvm.c
index b7564568dc..687d1e25fb 100644
--- a/hw/intc/arm_gic_kvm.c
+++ b/hw/intc/arm_gic_kvm.c
@@ -120,7 +120,7 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
         sysbus_init_irq(sbd, &s->parent_irq[i]);
     }
     /* Distributor */
-    memory_region_init_reservation(&s->iomem, "kvm-gic_dist", 0x1000);
+    memory_region_init_reservation(&s->iomem, NULL, "kvm-gic_dist", 0x1000);
     sysbus_init_mmio(sbd, &s->iomem);
     kvm_arm_register_device(&s->iomem,
                             (KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
@@ -129,7 +129,7 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
      * provide the "interface for core #N" memory regions, because
      * cores with a VGIC don't have those.
      */
-    memory_region_init_reservation(&s->cpuiomem[0], "kvm-gic_cpu", 0x1000);
+    memory_region_init_reservation(&s->cpuiomem[0], NULL, "kvm-gic_cpu", 0x1000);
     sysbus_init_mmio(sbd, &s->cpuiomem[0]);
     kvm_arm_register_device(&s->cpuiomem[0],
                             (KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index 25fa43cb2d..74baa728ca 100644
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -487,17 +487,17 @@ static void armv7m_nvic_realize(DeviceState *dev, Error **errp)
      * We use overlaying to put the GIC like registers
      * over the top of the system control register region.
      */
-    memory_region_init(&s->container, "nvic", 0x1000);
+    memory_region_init(&s->container, NULL, "nvic", 0x1000);
     /* The system register region goes at the bottom of the priority
      * stack as it covers the whole page.
      */
-    memory_region_init_io(&s->sysregmem, &nvic_sysreg_ops, s,
+    memory_region_init_io(&s->sysregmem, NULL, &nvic_sysreg_ops, s,
                           "nvic_sysregs", 0x1000);
     memory_region_add_subregion(&s->container, 0, &s->sysregmem);
     /* Alias the GIC region so we can get only the section of it
      * we need, and layer it on top of the system register region.
      */
-    memory_region_init_alias(&s->gic_iomem_alias, "nvic-gic", &s->gic.iomem,
+    memory_region_init_alias(&s->gic_iomem_alias, NULL, "nvic-gic", &s->gic.iomem,
                              0x100, 0xc00);
     memory_region_add_subregion_overlap(&s->container, 0x100,
                                         &s->gic_iomem_alias, 1);
diff --git a/hw/intc/etraxfs_pic.c b/hw/intc/etraxfs_pic.c
index 635103c001..81e1ab9532 100644
--- a/hw/intc/etraxfs_pic.c
+++ b/hw/intc/etraxfs_pic.c
@@ -146,7 +146,7 @@ static int etraxfs_pic_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->parent_irq);
     sysbus_init_irq(dev, &s->parent_nmi);
 
-    memory_region_init_io(&s->mmio, &pic_ops, s, "etraxfs-pic", R_MAX * 4);
+    memory_region_init_io(&s->mmio, NULL, &pic_ops, s, "etraxfs-pic", R_MAX * 4);
     sysbus_init_mmio(dev, &s->mmio);
     return 0;
 }
diff --git a/hw/intc/exynos4210_combiner.c b/hw/intc/exynos4210_combiner.c
index 6874287302..644d6b3cb1 100644
--- a/hw/intc/exynos4210_combiner.c
+++ b/hw/intc/exynos4210_combiner.c
@@ -417,7 +417,7 @@ static int exynos4210_combiner_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->output_irq[i]);
     }
 
-    memory_region_init_io(&s->iomem, &exynos4210_combiner_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_combiner_ops, s,
             "exynos4210-combiner", IIC_REGION_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/intc/exynos4210_gic.c b/hw/intc/exynos4210_gic.c
index bad6dde652..f9c4218c12 100644
--- a/hw/intc/exynos4210_gic.c
+++ b/hw/intc/exynos4210_gic.c
@@ -299,15 +299,15 @@ static int exynos4210_gic_init(SysBusDevice *dev)
     qdev_init_gpio_in(&s->busdev.qdev, exynos4210_gic_set_irq,
                       EXYNOS4210_GIC_NIRQ - 32);
 
-    memory_region_init(&s->cpu_container, "exynos4210-cpu-container",
+    memory_region_init(&s->cpu_container, NULL, "exynos4210-cpu-container",
             EXYNOS4210_EXT_GIC_CPU_REGION_SIZE);
-    memory_region_init(&s->dist_container, "exynos4210-dist-container",
+    memory_region_init(&s->dist_container, NULL, "exynos4210-dist-container",
             EXYNOS4210_EXT_GIC_DIST_REGION_SIZE);
 
     for (i = 0; i < s->num_cpu; i++) {
         /* Map CPU interface per SMP Core */
         sprintf(cpu_alias_name, "%s%x", cpu_prefix, i);
-        memory_region_init_alias(&s->cpu_alias[i],
+        memory_region_init_alias(&s->cpu_alias[i], NULL,
                                  cpu_alias_name,
                                  sysbus_mmio_get_region(busdev, 1),
                                  0,
@@ -317,7 +317,7 @@ static int exynos4210_gic_init(SysBusDevice *dev)
 
         /* Map Distributor per SMP Core */
         sprintf(dist_alias_name, "%s%x", dist_prefix, i);
-        memory_region_init_alias(&s->dist_alias[i],
+        memory_region_init_alias(&s->dist_alias[i], NULL,
                                  dist_alias_name,
                                  sysbus_mmio_get_region(busdev, 0),
                                  0,
diff --git a/hw/intc/grlib_irqmp.c b/hw/intc/grlib_irqmp.c
index 68dfe6a4bb..f933e6affa 100644
--- a/hw/intc/grlib_irqmp.c
+++ b/hw/intc/grlib_irqmp.c
@@ -344,7 +344,7 @@ static int grlib_irqmp_init(SysBusDevice *dev)
         return -1;
     }
 
-    memory_region_init_io(&irqmp->iomem, &grlib_irqmp_ops, irqmp,
+    memory_region_init_io(&irqmp->iomem, NULL, &grlib_irqmp_ops, irqmp,
                           "irqmp", IRQMP_REG_SIZE);
 
     irqmp->state = g_malloc0(sizeof *irqmp->state);
diff --git a/hw/intc/heathrow_pic.c b/hw/intc/heathrow_pic.c
index beb9661182..9818f2430c 100644
--- a/hw/intc/heathrow_pic.c
+++ b/hw/intc/heathrow_pic.c
@@ -205,7 +205,7 @@ qemu_irq *heathrow_pic_init(MemoryRegion **pmem,
     s = g_malloc0(sizeof(HeathrowPICS));
     /* only 1 CPU */
     s->irqs = irqs[0];
-    memory_region_init_io(&s->mem, &heathrow_pic_ops, s,
+    memory_region_init_io(&s->mem, NULL, &heathrow_pic_ops, s,
                           "heathrow-pic", 0x1000);
     *pmem = &s->mem;
 
diff --git a/hw/intc/i8259.c b/hw/intc/i8259.c
index 192a0ba68f..13250f19e2 100644
--- a/hw/intc/i8259.c
+++ b/hw/intc/i8259.c
@@ -417,8 +417,8 @@ static void pic_realize(DeviceState *dev, Error **err)
     PICCommonState *s = PIC_COMMON(dev);
     PICClass *pc = PIC_GET_CLASS(dev);
 
-    memory_region_init_io(&s->base_io, &pic_base_ioport_ops, s, "pic", 2);
-    memory_region_init_io(&s->elcr_io, &pic_elcr_ioport_ops, s, "elcr", 1);
+    memory_region_init_io(&s->base_io, NULL, &pic_base_ioport_ops, s, "pic", 2);
+    memory_region_init_io(&s->elcr_io, NULL, &pic_elcr_ioport_ops, s, "elcr", 1);
 
     qdev_init_gpio_out(dev, s->int_out, ARRAY_SIZE(s->int_out));
     qdev_init_gpio_in(dev, pic_set_irq, 8);
diff --git a/hw/intc/imx_avic.c b/hw/intc/imx_avic.c
index ff45dcdc0d..870d56f1fd 100644
--- a/hw/intc/imx_avic.c
+++ b/hw/intc/imx_avic.c
@@ -372,7 +372,7 @@ static int imx_avic_init(SysBusDevice *dev)
 {
     IMXAVICState *s = FROM_SYSBUS(IMXAVICState, dev);
 
-    memory_region_init_io(&s->iomem, &imx_avic_ops, s, "imx_avic", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &imx_avic_ops, s, "imx_avic", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
     qdev_init_gpio_in(&dev->qdev, imx_avic_set_irq, IMX_AVIC_NUM_IRQS);
diff --git a/hw/intc/ioapic.c b/hw/intc/ioapic.c
index c6f09f4331..7299b50521 100644
--- a/hw/intc/ioapic.c
+++ b/hw/intc/ioapic.c
@@ -227,7 +227,7 @@ static const MemoryRegionOps ioapic_io_ops = {
 
 static void ioapic_init(IOAPICCommonState *s, int instance_no)
 {
-    memory_region_init_io(&s->io_memory, &ioapic_io_ops, s, "ioapic", 0x1000);
+    memory_region_init_io(&s->io_memory, NULL, &ioapic_io_ops, s, "ioapic", 0x1000);
 
     qdev_init_gpio_in(&s->busdev.qdev, ioapic_set_irq, IOAPIC_NUM_PINS);
 
diff --git a/hw/intc/omap_intc.c b/hw/intc/omap_intc.c
index 875eba4e3e..00cb6ca4f7 100644
--- a/hw/intc/omap_intc.c
+++ b/hw/intc/omap_intc.c
@@ -367,7 +367,7 @@ static int omap_intc_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->parent_intr[0]);
     sysbus_init_irq(dev, &s->parent_intr[1]);
     qdev_init_gpio_in(&dev->qdev, omap_set_intr, s->nbanks * 32);
-    memory_region_init_io(&s->mmio, &omap_inth_mem_ops, s,
+    memory_region_init_io(&s->mmio, NULL, &omap_inth_mem_ops, s,
                           "omap-intc", s->size);
     sysbus_init_mmio(dev, &s->mmio);
     return 0;
@@ -609,7 +609,7 @@ static int omap2_intc_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->parent_intr[0]);
     sysbus_init_irq(dev, &s->parent_intr[1]);
     qdev_init_gpio_in(&dev->qdev, omap_set_intr_noedge, s->nbanks * 32);
-    memory_region_init_io(&s->mmio, &omap2_inth_mem_ops, s,
+    memory_region_init_io(&s->mmio, NULL, &omap2_inth_mem_ops, s,
                           "omap2-intc", 0x1000);
     sysbus_init_mmio(dev, &s->mmio);
     return 0;
diff --git a/hw/intc/openpic.c b/hw/intc/openpic.c
index a26c641699..b9e025ffd2 100644
--- a/hw/intc/openpic.c
+++ b/hw/intc/openpic.c
@@ -1516,7 +1516,7 @@ static void map_list(OpenPICState *opp, const MemReg *list, int *count)
     while (list->name) {
         assert(*count < ARRAY_SIZE(opp->sub_io_mem));
 
-        memory_region_init_io(&opp->sub_io_mem[*count], list->ops, opp,
+        memory_region_init_io(&opp->sub_io_mem[*count], NULL, list->ops, opp,
                               list->name, list->size);
 
         memory_region_add_subregion(&opp->mem, list->start_addr,
@@ -1531,7 +1531,7 @@ static void openpic_init(Object *obj)
 {
     OpenPICState *opp = OPENPIC(obj);
 
-    memory_region_init(&opp->mem, "openpic", 0x40000);
+    memory_region_init(&opp->mem, NULL, "openpic", 0x40000);
 }
 
 static void openpic_realize(DeviceState *dev, Error **errp)
diff --git a/hw/intc/openpic_kvm.c b/hw/intc/openpic_kvm.c
index 6775879e0f..dc08031f89 100644
--- a/hw/intc/openpic_kvm.c
+++ b/hw/intc/openpic_kvm.c
@@ -155,7 +155,7 @@ static void kvm_openpic_init(Object *obj)
 {
     KVMOpenPICState *opp = KVM_OPENPIC(obj);
 
-    memory_region_init_io(&opp->mem, &kvm_openpic_mem_ops, opp,
+    memory_region_init_io(&opp->mem, NULL, &kvm_openpic_mem_ops, opp,
                           "kvm-openpic", 0x40000);
 }
 
diff --git a/hw/intc/pl190.c b/hw/intc/pl190.c
index 9610673d94..5f0f9b7514 100644
--- a/hw/intc/pl190.c
+++ b/hw/intc/pl190.c
@@ -236,7 +236,7 @@ static int pl190_init(SysBusDevice *dev)
 {
     pl190_state *s = FROM_SYSBUS(pl190_state, dev);
 
-    memory_region_init_io(&s->iomem, &pl190_ops, s, "pl190", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl190_ops, s, "pl190", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     qdev_init_gpio_in(&dev->qdev, pl190_set_irq, 32);
     sysbus_init_irq(dev, &s->irq);
diff --git a/hw/intc/puv3_intc.c b/hw/intc/puv3_intc.c
index 0cd5e9eae0..b327f0e8d7 100644
--- a/hw/intc/puv3_intc.c
+++ b/hw/intc/puv3_intc.c
@@ -106,7 +106,7 @@ static int puv3_intc_init(SysBusDevice *dev)
     s->reg_ICMR = 0;
     s->reg_ICPR = 0;
 
-    memory_region_init_io(&s->iomem, &puv3_intc_ops, s, "puv3_intc",
+    memory_region_init_io(&s->iomem, NULL, &puv3_intc_ops, s, "puv3_intc",
             PUV3_REGS_OFFSET);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/intc/realview_gic.c b/hw/intc/realview_gic.c
index 0ec30caa06..1731a70b45 100644
--- a/hw/intc/realview_gic.c
+++ b/hw/intc/realview_gic.c
@@ -43,7 +43,7 @@ static int realview_gic_init(SysBusDevice *dev)
     /* Pass through inbound GPIO lines to the GIC */
     qdev_init_gpio_in(&s->busdev.qdev, realview_gic_set_irq, numirq - 32);
 
-    memory_region_init(&s->container, "realview-gic-container", 0x2000);
+    memory_region_init(&s->container, NULL, "realview-gic-container", 0x2000);
     memory_region_add_subregion(&s->container, 0,
                                 sysbus_mmio_get_region(busdev, 1));
     memory_region_add_subregion(&s->container, 0x1000,
diff --git a/hw/intc/sh_intc.c b/hw/intc/sh_intc.c
index 050bfb63ce..f397950cbb 100644
--- a/hw/intc/sh_intc.c
+++ b/hw/intc/sh_intc.c
@@ -319,11 +319,11 @@ static unsigned int sh_intc_register(MemoryRegion *sysmem,
 
 #define SH_INTC_IOMEM_FORMAT "interrupt-controller-%s-%s-%s"
     snprintf(name, sizeof(name), SH_INTC_IOMEM_FORMAT, type, action, "p4");
-    memory_region_init_alias(iomem_p4, name, iomem, INTC_A7(address), 4);
+    memory_region_init_alias(iomem_p4, NULL, name, iomem, INTC_A7(address), 4);
     memory_region_add_subregion(sysmem, P4ADDR(address), iomem_p4);
 
     snprintf(name, sizeof(name), SH_INTC_IOMEM_FORMAT, type, action, "a7");
-    memory_region_init_alias(iomem_a7, name, iomem, INTC_A7(address), 4);
+    memory_region_init_alias(iomem_a7, NULL, name, iomem, INTC_A7(address), 4);
     memory_region_add_subregion(sysmem, A7ADDR(address), iomem_a7);
 #undef SH_INTC_IOMEM_FORMAT
 
@@ -466,7 +466,7 @@ int sh_intc_init(MemoryRegion *sysmem,
 
     desc->irqs = qemu_allocate_irqs(sh_intc_set_irq, desc, nr_sources);
  
-    memory_region_init_io(&desc->iomem, &sh_intc_ops, desc,
+    memory_region_init_io(&desc->iomem, NULL, &sh_intc_ops, desc,
                           "interrupt-controller", 0x100000000ULL);
 
 #define INT_REG_PARAMS(reg_struct, type, action, j) \
diff --git a/hw/intc/slavio_intctl.c b/hw/intc/slavio_intctl.c
index b367752fd3..716e36d744 100644
--- a/hw/intc/slavio_intctl.c
+++ b/hw/intc/slavio_intctl.c
@@ -426,7 +426,7 @@ static int slavio_intctl_init1(SysBusDevice *dev)
     char slave_name[45];
 
     qdev_init_gpio_in(&dev->qdev, slavio_set_irq_all, 32 + MAX_CPUS);
-    memory_region_init_io(&s->iomem, &slavio_intctlm_mem_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &slavio_intctlm_mem_ops, s,
                           "master-interrupt-controller", INTCTLM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
@@ -436,7 +436,7 @@ static int slavio_intctl_init1(SysBusDevice *dev)
         for (j = 0; j < MAX_PILS; j++) {
             sysbus_init_irq(dev, &s->cpu_irqs[i][j]);
         }
-        memory_region_init_io(&s->slaves[i].iomem, &slavio_intctl_mem_ops,
+        memory_region_init_io(&s->slaves[i].iomem, NULL, &slavio_intctl_mem_ops,
                               &s->slaves[i], slave_name, INTCTL_SIZE);
         sysbus_init_mmio(dev, &s->slaves[i].iomem);
         s->slaves[i].cpu = i;
diff --git a/hw/intc/xilinx_intc.c b/hw/intc/xilinx_intc.c
index 297f53759c..9ba35f6638 100644
--- a/hw/intc/xilinx_intc.c
+++ b/hw/intc/xilinx_intc.c
@@ -160,7 +160,7 @@ static int xilinx_intc_init(SysBusDevice *dev)
     qdev_init_gpio_in(&dev->qdev, irq_handler, 32);
     sysbus_init_irq(dev, &p->parent_irq);
 
-    memory_region_init_io(&p->mmio, &pic_ops, p, "xlnx.xps-intc", R_MAX * 4);
+    memory_region_init_io(&p->mmio, NULL, &pic_ops, p, "xlnx.xps-intc", R_MAX * 4);
     sysbus_init_mmio(dev, &p->mmio);
     return 0;
 }
diff --git a/hw/isa/apm.c b/hw/isa/apm.c
index 5f21d21473..daed6f1b51 100644
--- a/hw/isa/apm.c
+++ b/hw/isa/apm.c
@@ -96,7 +96,7 @@ void apm_init(PCIDevice *dev, APMState *apm, apm_ctrl_changed_t callback,
     apm->arg = arg;
 
     /* ioport 0xb2, 0xb3 */
-    memory_region_init_io(&apm->io, &apm_ops, apm, "apm-io", 2);
+    memory_region_init_io(&apm->io, NULL, &apm_ops, apm, "apm-io", 2);
     memory_region_add_subregion(pci_address_space_io(dev), APM_CNT_IOPORT,
                                 &apm->io);
 }
diff --git a/hw/isa/i82378.c b/hw/isa/i82378.c
index a24cb98cba..90f36d591c 100644
--- a/hw/isa/i82378.c
+++ b/hw/isa/i82378.c
@@ -221,10 +221,10 @@ static int pci_i82378_init(PCIDevice *dev)
 
     pci_conf[PCI_INTERRUPT_PIN] = 1; /* interrupt pin 0 */
 
-    memory_region_init_io(&s->io, &i82378_io_ops, s, "i82378-io", 0x00010000);
+    memory_region_init_io(&s->io, NULL, &i82378_io_ops, s, "i82378-io", 0x00010000);
     pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->io);
 
-    memory_region_init_io(&s->mem, &i82378_mem_ops, s, "i82378-mem", 0x01000000);
+    memory_region_init_io(&s->mem, NULL, &i82378_mem_ops, s, "i82378-mem", 0x01000000);
     pci_register_bar(dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->mem);
 
     /* Make I/O address read only */
diff --git a/hw/isa/isa_mmio.c b/hw/isa/isa_mmio.c
index d4dbf13831..00ae8ebc2e 100644
--- a/hw/isa/isa_mmio.c
+++ b/hw/isa/isa_mmio.c
@@ -69,7 +69,7 @@ static const MemoryRegionOps isa_mmio_ops = {
 
 void isa_mmio_setup(MemoryRegion *mr, hwaddr size)
 {
-    memory_region_init_io(mr, &isa_mmio_ops, NULL, "isa-mmio", size);
+    memory_region_init_io(mr, NULL, &isa_mmio_ops, NULL, "isa-mmio", size);
 }
 
 void isa_mmio_init(hwaddr base, hwaddr size)
diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
index 461ab7caf3..82f8ea6264 100644
--- a/hw/isa/lpc_ich9.c
+++ b/hw/isa/lpc_ich9.c
@@ -535,7 +535,7 @@ static int ich9_lpc_initfn(PCIDevice *d)
     pci_set_long(d->wmask + ICH9_LPC_PMBASE,
                  ICH9_LPC_PMBASE_BASE_ADDRESS_MASK);
 
-    memory_region_init_io(&lpc->rbca_mem, &rbca_mmio_ops, lpc,
+    memory_region_init_io(&lpc->rbca_mem, NULL, &rbca_mmio_ops, lpc,
                             "lpc-rbca-mmio", ICH9_CC_SIZE);
 
     lpc->isa_bus = isa_bus;
@@ -546,7 +546,7 @@ static int ich9_lpc_initfn(PCIDevice *d)
     lpc->machine_ready.notify = ich9_lpc_machine_ready;
     qemu_add_machine_init_done_notifier(&lpc->machine_ready);
 
-    memory_region_init_io(&lpc->rst_cnt_mem, &ich9_rst_cnt_ops, lpc,
+    memory_region_init_io(&lpc->rst_cnt_mem, NULL, &ich9_rst_cnt_ops, lpc,
                           "lpc-reset-control", 1);
     memory_region_add_subregion_overlap(pci_address_space_io(d),
                                         ICH9_RST_CNT_IOPORT, &lpc->rst_cnt_mem,
diff --git a/hw/isa/pc87312.c b/hw/isa/pc87312.c
index cc426df7f8..7b3e7fb955 100644
--- a/hw/isa/pc87312.c
+++ b/hw/isa/pc87312.c
@@ -352,7 +352,7 @@ static void pc87312_initfn(Object *obj)
 {
     PC87312State *s = PC87312(obj);
 
-    memory_region_init_io(&s->io, &pc87312_io_ops, s, "pc87312", 2);
+    memory_region_init_io(&s->io, NULL, &pc87312_io_ops, s, "pc87312", 2);
 }
 
 static const VMStateDescription vmstate_pc87312 = {
diff --git a/hw/isa/vt82c686.c b/hw/isa/vt82c686.c
index e5cd4cdf79..1f63197d82 100644
--- a/hw/isa/vt82c686.c
+++ b/hw/isa/vt82c686.c
@@ -356,7 +356,7 @@ static int vt82c686b_pm_initfn(PCIDevice *dev)
 
     apm_init(dev, &s->apm, NULL, s);
 
-    memory_region_init(&s->io, "vt82c686-pm", 64);
+    memory_region_init(&s->io, NULL, "vt82c686-pm", 64);
     memory_region_set_enabled(&s->io, false);
     memory_region_add_subregion(get_system_io(), 0, &s->io);
 
@@ -443,8 +443,8 @@ static int vt82c686b_initfn(PCIDevice *d)
        }
     }
 
-    memory_region_init_io(&vt82c->superio, &superio_ops, &vt82c->superio_conf,
-                          "superio", 2);
+    memory_region_init_io(&vt82c->superio, NULL, &superio_ops,
+                          &vt82c->superio_conf, "superio", 2);
     memory_region_set_enabled(&vt82c->superio, false);
     /* The floppy also uses 0x3f0 and 0x3f1.
      * But we do not emulate a floppy, so just set it here. */
diff --git a/hw/lm32/lm32_boards.c b/hw/lm32/lm32_boards.c
index 1ca94980fb..62003b8585 100644
--- a/hw/lm32/lm32_boards.c
+++ b/hw/lm32/lm32_boards.c
@@ -106,7 +106,7 @@ static void lm32_evr_init(QEMUMachineInitArgs *args)
 
     reset_info->flash_base = flash_base;
 
-    memory_region_init_ram(phys_ram, "lm32_evr.sdram", ram_size);
+    memory_region_init_ram(phys_ram, NULL, "lm32_evr.sdram", ram_size);
     vmstate_register_ram_global(phys_ram);
     memory_region_add_subregion(address_space_mem, ram_base, phys_ram);
 
@@ -203,7 +203,7 @@ static void lm32_uclinux_init(QEMUMachineInitArgs *args)
 
     reset_info->flash_base = flash_base;
 
-    memory_region_init_ram(phys_ram, "lm32_uclinux.sdram", ram_size);
+    memory_region_init_ram(phys_ram, NULL, "lm32_uclinux.sdram", ram_size);
     vmstate_register_ram_global(phys_ram);
     memory_region_add_subregion(address_space_mem, ram_base, phys_ram);
 
diff --git a/hw/lm32/milkymist.c b/hw/lm32/milkymist.c
index cca93748aa..7ceedb814f 100644
--- a/hw/lm32/milkymist.c
+++ b/hw/lm32/milkymist.c
@@ -112,7 +112,7 @@ milkymist_init(QEMUMachineInitArgs *args)
 
     cpu_lm32_set_phys_msb_ignore(env, 1);
 
-    memory_region_init_ram(phys_sdram, "milkymist.sdram", sdram_size);
+    memory_region_init_ram(phys_sdram, NULL, "milkymist.sdram", sdram_size);
     vmstate_register_ram_global(phys_sdram);
     memory_region_add_subregion(address_space_mem, sdram_base, phys_sdram);
 
diff --git a/hw/m68k/an5206.c b/hw/m68k/an5206.c
index c4a5626a53..0c03a87abc 100644
--- a/hw/m68k/an5206.c
+++ b/hw/m68k/an5206.c
@@ -49,12 +49,12 @@ static void an5206_init(QEMUMachineInitArgs *args)
     env->rambar0 = AN5206_RAMBAR_ADDR | 1;
 
     /* DRAM at address zero */
-    memory_region_init_ram(ram, "an5206.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "an5206.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, 0, ram);
 
     /* Internal SRAM.  */
-    memory_region_init_ram(sram, "an5206.sram", 512);
+    memory_region_init_ram(sram, NULL, "an5206.sram", 512);
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(address_space_mem, AN5206_RAMBAR_ADDR, sram);
 
diff --git a/hw/m68k/dummy_m68k.c b/hw/m68k/dummy_m68k.c
index 544d56b59d..f4ed7c6cc5 100644
--- a/hw/m68k/dummy_m68k.c
+++ b/hw/m68k/dummy_m68k.c
@@ -40,7 +40,7 @@ static void dummy_m68k_init(QEMUMachineInitArgs *args)
     env->vbr = 0;
 
     /* RAM at address zero */
-    memory_region_init_ram(ram, "dummy_m68k.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "dummy_m68k.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, 0, ram);
 
diff --git a/hw/m68k/mcf5206.c b/hw/m68k/mcf5206.c
index bcc619d74b..1727a4685c 100644
--- a/hw/m68k/mcf5206.c
+++ b/hw/m68k/mcf5206.c
@@ -532,7 +532,7 @@ qemu_irq *mcf5206_init(MemoryRegion *sysmem, uint32_t base, M68kCPU *cpu)
 
     s = (m5206_mbar_state *)g_malloc0(sizeof(m5206_mbar_state));
 
-    memory_region_init_io(&s->iomem, &m5206_mbar_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &m5206_mbar_ops, s,
                           "mbar", 0x00001000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
diff --git a/hw/m68k/mcf5208.c b/hw/m68k/mcf5208.c
index 05efde7ceb..9cf000f4ce 100644
--- a/hw/m68k/mcf5208.c
+++ b/hw/m68k/mcf5208.c
@@ -172,14 +172,14 @@ static void mcf5208_sys_init(MemoryRegion *address_space, qemu_irq *pic)
     int i;
 
     /* SDRAMC.  */
-    memory_region_init_io(iomem, &m5208_sys_ops, NULL, "m5208-sys", 0x00004000);
+    memory_region_init_io(iomem, NULL, &m5208_sys_ops, NULL, "m5208-sys", 0x00004000);
     memory_region_add_subregion(address_space, 0xfc0a8000, iomem);
     /* Timers.  */
     for (i = 0; i < 2; i++) {
         s = (m5208_timer_state *)g_malloc0(sizeof(m5208_timer_state));
         bh = qemu_bh_new(m5208_timer_trigger, s);
         s->timer = ptimer_init(bh);
-        memory_region_init_io(&s->iomem, &m5208_timer_ops, s,
+        memory_region_init_io(&s->iomem, NULL, &m5208_timer_ops, s,
                               "m5208-timer", 0x00004000);
         memory_region_add_subregion(address_space, 0xfc080000 + 0x4000 * i,
                                     &s->iomem);
@@ -217,12 +217,12 @@ static void mcf5208evb_init(QEMUMachineInitArgs *args)
     /* TODO: Configure BARs.  */
 
     /* DRAM at 0x40000000 */
-    memory_region_init_ram(ram, "mcf5208.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "mcf5208.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, 0x40000000, ram);
 
     /* Internal SRAM.  */
-    memory_region_init_ram(sram, "mcf5208.sram", 16384);
+    memory_region_init_ram(sram, NULL, "mcf5208.sram", 16384);
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(address_space_mem, 0x80000000, sram);
 
diff --git a/hw/m68k/mcf_intc.c b/hw/m68k/mcf_intc.c
index cfe660d0a4..621423c3e4 100644
--- a/hw/m68k/mcf_intc.c
+++ b/hw/m68k/mcf_intc.c
@@ -147,7 +147,7 @@ qemu_irq *mcf_intc_init(MemoryRegion *sysmem,
     s->cpu = cpu;
     mcf_intc_reset(s);
 
-    memory_region_init_io(&s->iomem, &mcf_intc_ops, s, "mcf", 0x100);
+    memory_region_init_io(&s->iomem, NULL, &mcf_intc_ops, s, "mcf", 0x100);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     return qemu_allocate_irqs(mcf_intc_set_irq, s, 64);
diff --git a/hw/microblaze/petalogix_ml605_mmu.c b/hw/microblaze/petalogix_ml605_mmu.c
index 334046808f..989da25dec 100644
--- a/hw/microblaze/petalogix_ml605_mmu.c
+++ b/hw/microblaze/petalogix_ml605_mmu.c
@@ -98,12 +98,12 @@ petalogix_ml605_init(QEMUMachineInitArgs *args)
     env = &cpu->env;
 
     /* Attach emulated BRAM through the LMB.  */
-    memory_region_init_ram(phys_lmb_bram, "petalogix_ml605.lmb_bram",
+    memory_region_init_ram(phys_lmb_bram, NULL, "petalogix_ml605.lmb_bram",
                            LMB_BRAM_SIZE);
     vmstate_register_ram_global(phys_lmb_bram);
     memory_region_add_subregion(address_space_mem, 0x00000000, phys_lmb_bram);
 
-    memory_region_init_ram(phys_ram, "petalogix_ml605.ram", ram_size);
+    memory_region_init_ram(phys_ram, NULL, "petalogix_ml605.ram", ram_size);
     vmstate_register_ram_global(phys_ram);
     memory_region_add_subregion(address_space_mem, ddr_base, phys_ram);
 
diff --git a/hw/microblaze/petalogix_s3adsp1800_mmu.c b/hw/microblaze/petalogix_s3adsp1800_mmu.c
index b3bcd4ea5e..a461494439 100644
--- a/hw/microblaze/petalogix_s3adsp1800_mmu.c
+++ b/hw/microblaze/petalogix_s3adsp1800_mmu.c
@@ -80,12 +80,12 @@ petalogix_s3adsp1800_init(QEMUMachineInitArgs *args)
     env = &cpu->env;
 
     /* Attach emulated BRAM through the LMB.  */
-    memory_region_init_ram(phys_lmb_bram,
+    memory_region_init_ram(phys_lmb_bram, NULL,
                            "petalogix_s3adsp1800.lmb_bram", LMB_BRAM_SIZE);
     vmstate_register_ram_global(phys_lmb_bram);
     memory_region_add_subregion(sysmem, 0x00000000, phys_lmb_bram);
 
-    memory_region_init_ram(phys_ram, "petalogix_s3adsp1800.ram", ram_size);
+    memory_region_init_ram(phys_ram, NULL, "petalogix_s3adsp1800.ram", ram_size);
     vmstate_register_ram_global(phys_ram);
     memory_region_add_subregion(sysmem, ddr_base, phys_ram);
 
diff --git a/hw/mips/gt64xxx_pci.c b/hw/mips/gt64xxx_pci.c
index 189e865a65..d2739eb261 100644
--- a/hw/mips/gt64xxx_pci.c
+++ b/hw/mips/gt64xxx_pci.c
@@ -1108,7 +1108,7 @@ PCIBus *gt64120_register(qemu_irq *pic)
                                 get_system_memory(),
                                 get_system_io(),
                                 PCI_DEVFN(18, 0), 4, TYPE_PCI_BUS);
-    memory_region_init_io(&d->ISD_mem, &isd_mem_ops, d, "isd-mem", 0x1000);
+    memory_region_init_io(&d->ISD_mem, NULL, &isd_mem_ops, d, "isd-mem", 0x1000);
 
     pci_create_simple(phb->bus, PCI_DEVFN(0, 0), "gt64120_pci");
     return phb->bus;
diff --git a/hw/mips/mips_fulong2e.c b/hw/mips/mips_fulong2e.c
index 00c9071af1..7d198e7c69 100644
--- a/hw/mips/mips_fulong2e.c
+++ b/hw/mips/mips_fulong2e.c
@@ -300,9 +300,9 @@ static void mips_fulong2e_init(QEMUMachineInitArgs *args)
     bios_size = 1024 * 1024;
 
     /* allocate RAM */
-    memory_region_init_ram(ram, "fulong2e.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "fulong2e.ram", ram_size);
     vmstate_register_ram_global(ram);
-    memory_region_init_ram(bios, "fulong2e.bios", bios_size);
+    memory_region_init_ram(bios, NULL, "fulong2e.bios", bios_size);
     vmstate_register_ram_global(bios);
     memory_region_set_readonly(bios, true);
 
diff --git a/hw/mips/mips_jazz.c b/hw/mips/mips_jazz.c
index 2ad0c0b414..3eac63b2fc 100644
--- a/hw/mips/mips_jazz.c
+++ b/hw/mips/mips_jazz.c
@@ -152,14 +152,14 @@ static void mips_jazz_init(MemoryRegion *address_space,
     qemu_register_reset(main_cpu_reset, cpu);
 
     /* allocate RAM */
-    memory_region_init_ram(ram, "mips_jazz.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "mips_jazz.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space, 0, ram);
 
-    memory_region_init_ram(bios, "mips_jazz.bios", MAGNUM_BIOS_SIZE);
+    memory_region_init_ram(bios, NULL, "mips_jazz.bios", MAGNUM_BIOS_SIZE);
     vmstate_register_ram_global(bios);
     memory_region_set_readonly(bios, true);
-    memory_region_init_alias(bios2, "mips_jazz.bios", bios,
+    memory_region_init_alias(bios2, NULL, "mips_jazz.bios", bios,
                              0, MAGNUM_BIOS_SIZE);
     memory_region_add_subregion(address_space, 0x1fc00000LL, bios);
     memory_region_add_subregion(address_space, 0xfff00000LL, bios2);
@@ -188,7 +188,7 @@ static void mips_jazz_init(MemoryRegion *address_space,
     /* Chipset */
     rc4030_opaque = rc4030_init(env->irq[6], env->irq[3], &rc4030, &dmas,
                                 address_space);
-    memory_region_init_io(dma_dummy, &dma_dummy_ops, NULL, "dummy_dma", 0x1000);
+    memory_region_init_io(dma_dummy, NULL, &dma_dummy_ops, NULL, "dummy_dma", 0x1000);
     memory_region_add_subregion(address_space, 0x8000d000, dma_dummy);
 
     /* ISA devices */
@@ -216,7 +216,7 @@ static void mips_jazz_init(MemoryRegion *address_space,
         {
             /* Simple ROM, so user doesn't have to provide one */
             MemoryRegion *rom_mr = g_new(MemoryRegion, 1);
-            memory_region_init_ram(rom_mr, "g364fb.rom", 0x80000);
+            memory_region_init_ram(rom_mr, NULL, "g364fb.rom", 0x80000);
             vmstate_register_ram_global(rom_mr);
             memory_region_set_readonly(rom_mr, true);
             uint8_t *rom = memory_region_get_ram_ptr(rom_mr);
@@ -266,7 +266,7 @@ static void mips_jazz_init(MemoryRegion *address_space,
 
     /* Real time clock */
     rtc_init(isa_bus, 1980, NULL);
-    memory_region_init_io(rtc, &rtc_ops, NULL, "rtc", 0x1000);
+    memory_region_init_io(rtc, NULL, &rtc_ops, NULL, "rtc", 0x1000);
     memory_region_add_subregion(address_space, 0x80004000, rtc);
 
     /* Keyboard (i8042) */
diff --git a/hw/mips/mips_malta.c b/hw/mips/mips_malta.c
index 8a4459d0b2..c27ed0b8ed 100644
--- a/hw/mips/mips_malta.c
+++ b/hw/mips/mips_malta.c
@@ -446,11 +446,11 @@ static MaltaFPGAState *malta_fpga_init(MemoryRegion *address_space,
 
     s = (MaltaFPGAState *)g_malloc0(sizeof(MaltaFPGAState));
 
-    memory_region_init_io(&s->iomem, &malta_fpga_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &malta_fpga_ops, s,
                           "malta-fpga", 0x100000);
-    memory_region_init_alias(&s->iomem_lo, "malta-fpga",
+    memory_region_init_alias(&s->iomem_lo, NULL, "malta-fpga",
                              &s->iomem, 0, 0x900);
-    memory_region_init_alias(&s->iomem_hi, "malta-fpga",
+    memory_region_init_alias(&s->iomem_hi, NULL, "malta-fpga",
                              &s->iomem, 0xa00, 0x10000-0xa00);
 
     memory_region_add_subregion(address_space, base, &s->iomem_lo);
@@ -853,7 +853,7 @@ void mips_malta_init(QEMUMachineInitArgs *args)
                 ((unsigned int)ram_size / (1 << 20)));
         exit(1);
     }
-    memory_region_init_ram(ram, "mips_malta.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "mips_malta.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(system_memory, 0, ram);
 
@@ -927,7 +927,7 @@ void mips_malta_init(QEMUMachineInitArgs *args)
     }
 
     /* Map the BIOS at a 2nd physical location, as on the real board. */
-    memory_region_init_alias(bios_alias, "bios.1fc", bios, 0, BIOS_SIZE);
+    memory_region_init_alias(bios_alias, NULL, "bios.1fc", bios, 0, BIOS_SIZE);
     memory_region_add_subregion(system_memory, RESET_ADDRESS, bios_alias);
 
     /* Board ID = 0x420 (Malta Board with CoreLV)
diff --git a/hw/mips/mips_mipssim.c b/hw/mips/mips_mipssim.c
index d1681ec2fe..a10cf13a92 100644
--- a/hw/mips/mips_mipssim.c
+++ b/hw/mips/mips_mipssim.c
@@ -168,9 +168,9 @@ mips_mipssim_init(QEMUMachineInitArgs *args)
     qemu_register_reset(main_cpu_reset, reset_info);
 
     /* Allocate RAM. */
-    memory_region_init_ram(ram, "mips_mipssim.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "mips_mipssim.ram", ram_size);
     vmstate_register_ram_global(ram);
-    memory_region_init_ram(bios, "mips_mipssim.bios", BIOS_SIZE);
+    memory_region_init_ram(bios, NULL, "mips_mipssim.bios", BIOS_SIZE);
     vmstate_register_ram_global(bios);
     memory_region_set_readonly(bios, true);
 
diff --git a/hw/mips/mips_r4k.c b/hw/mips/mips_r4k.c
index 4646ab6db7..22beb0a67c 100644
--- a/hw/mips/mips_r4k.c
+++ b/hw/mips/mips_r4k.c
@@ -202,12 +202,12 @@ void mips_r4k_init(QEMUMachineInitArgs *args)
                 ((unsigned int)ram_size / (1 << 20)));
         exit(1);
     }
-    memory_region_init_ram(ram, "mips_r4k.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "mips_r4k.ram", ram_size);
     vmstate_register_ram_global(ram);
 
     memory_region_add_subregion(address_space_mem, 0, ram);
 
-    memory_region_init_io(iomem, &mips_qemu_ops, NULL, "mips-qemu", 0x10000);
+    memory_region_init_io(iomem, NULL, &mips_qemu_ops, NULL, "mips-qemu", 0x10000);
     memory_region_add_subregion(address_space_mem, 0x1fbf0000, iomem);
 
     /* Try to load a BIOS image. If this fails, we continue regardless,
@@ -229,7 +229,7 @@ void mips_r4k_init(QEMUMachineInitArgs *args)
 #endif
     if ((bios_size > 0) && (bios_size <= BIOS_SIZE)) {
         bios = g_new(MemoryRegion, 1);
-        memory_region_init_ram(bios, "mips_r4k.bios", BIOS_SIZE);
+        memory_region_init_ram(bios, NULL, "mips_r4k.bios", BIOS_SIZE);
         vmstate_register_ram_global(bios);
         memory_region_set_readonly(bios, true);
         memory_region_add_subregion(get_system_memory(), 0x1fc00000, bios);
diff --git a/hw/misc/a9scu.c b/hw/misc/a9scu.c
index 05897c2fa2..c8f26f923a 100644
--- a/hw/misc/a9scu.c
+++ b/hw/misc/a9scu.c
@@ -119,7 +119,7 @@ static void a9_scu_realize(DeviceState *dev, Error ** errp)
     A9SCUState *s = A9_SCU(dev);
     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
 
-    memory_region_init_io(&s->iomem, &a9_scu_ops, s, "a9-scu", 0x100);
+    memory_region_init_io(&s->iomem, NULL, &a9_scu_ops, s, "a9-scu", 0x100);
     sysbus_init_mmio(sbd, &s->iomem);
 }
 
diff --git a/hw/misc/applesmc.c b/hw/misc/applesmc.c
index 83468dc98f..ca4077f0b9 100644
--- a/hw/misc/applesmc.c
+++ b/hw/misc/applesmc.c
@@ -230,12 +230,12 @@ static void applesmc_isa_realize(DeviceState *dev, Error **errp)
 {
     AppleSMCState *s = APPLE_SMC(dev);
 
-    memory_region_init_io(&s->io_data, &applesmc_data_io_ops, s,
+    memory_region_init_io(&s->io_data, NULL, &applesmc_data_io_ops, s,
                           "applesmc-data", 4);
     isa_register_ioport(&s->parent_obj, &s->io_data,
                         s->iobase + APPLESMC_DATA_PORT);
 
-    memory_region_init_io(&s->io_cmd, &applesmc_cmd_io_ops, s,
+    memory_region_init_io(&s->io_cmd, NULL, &applesmc_cmd_io_ops, s,
                           "applesmc-cmd", 4);
     isa_register_ioport(&s->parent_obj, &s->io_cmd,
                         s->iobase + APPLESMC_CMD_PORT);
diff --git a/hw/misc/arm_l2x0.c b/hw/misc/arm_l2x0.c
index eb4427d9c4..954343f467 100644
--- a/hw/misc/arm_l2x0.c
+++ b/hw/misc/arm_l2x0.c
@@ -157,7 +157,7 @@ static int l2x0_priv_init(SysBusDevice *dev)
 {
     l2x0_state *s = FROM_SYSBUS(l2x0_state, dev);
 
-    memory_region_init_io(&s->iomem, &l2x0_mem_ops, s, "l2x0_cc", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &l2x0_mem_ops, s, "l2x0_cc", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
 }
diff --git a/hw/misc/arm_sysctl.c b/hw/misc/arm_sysctl.c
index c8b55a8349..9b07355c32 100644
--- a/hw/misc/arm_sysctl.c
+++ b/hw/misc/arm_sysctl.c
@@ -589,7 +589,7 @@ static void arm_sysctl_init(Object *obj)
     SysBusDevice *sd = SYS_BUS_DEVICE(obj);
     arm_sysctl_state *s = FROM_SYSBUS(arm_sysctl_state, sd);
 
-    memory_region_init_io(&s->iomem, &arm_sysctl_ops, s, "arm-sysctl", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &arm_sysctl_ops, s, "arm-sysctl", 0x1000);
     sysbus_init_mmio(sd, &s->iomem);
     qdev_init_gpio_in(dev, arm_sysctl_gpio_set, 2);
     qdev_init_gpio_out(dev, &s->pl110_mux_ctrl, 1);
diff --git a/hw/misc/debugexit.c b/hw/misc/debugexit.c
index ee254e46d2..e3a13f045c 100644
--- a/hw/misc/debugexit.c
+++ b/hw/misc/debugexit.c
@@ -40,7 +40,7 @@ static void debug_exit_realizefn(DeviceState *d, Error **errp)
     ISADevice *dev = ISA_DEVICE(d);
     ISADebugExitState *isa = ISA_DEBUG_EXIT_DEVICE(d);
 
-    memory_region_init_io(&isa->io, &debug_exit_ops, isa,
+    memory_region_init_io(&isa->io, NULL, &debug_exit_ops, isa,
                           TYPE_ISA_DEBUG_EXIT_DEVICE, isa->iosize);
     memory_region_add_subregion(isa_address_space_io(dev),
                                 isa->iobase, &isa->io);
diff --git a/hw/misc/eccmemctl.c b/hw/misc/eccmemctl.c
index 6f4a407cbf..71d62cc239 100644
--- a/hw/misc/eccmemctl.c
+++ b/hw/misc/eccmemctl.c
@@ -296,11 +296,11 @@ static int ecc_init1(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
     s->regs[0] = s->version;
-    memory_region_init_io(&s->iomem, &ecc_mem_ops, s, "ecc", ECC_SIZE);
+    memory_region_init_io(&s->iomem, NULL, &ecc_mem_ops, s, "ecc", ECC_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
     if (s->version == ECC_MCC) { // SS-600MP only
-        memory_region_init_io(&s->iomem_diag, &ecc_diag_mem_ops, s,
+        memory_region_init_io(&s->iomem_diag, NULL, &ecc_diag_mem_ops, s,
                               "ecc.diag", ECC_DIAG_SIZE);
         sysbus_init_mmio(dev, &s->iomem_diag);
     }
diff --git a/hw/misc/exynos4210_pmu.c b/hw/misc/exynos4210_pmu.c
index ba5aa8d0e4..465e72f933 100644
--- a/hw/misc/exynos4210_pmu.c
+++ b/hw/misc/exynos4210_pmu.c
@@ -458,7 +458,7 @@ static int exynos4210_pmu_init(SysBusDevice *dev)
     Exynos4210PmuState *s = FROM_SYSBUS(Exynos4210PmuState, dev);
 
     /* memory mapping */
-    memory_region_init_io(&s->iomem, &exynos4210_pmu_ops, s, "exynos4210.pmu",
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_pmu_ops, s, "exynos4210.pmu",
                           EXYNOS4210_PMU_REGS_MEM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
diff --git a/hw/misc/imx_ccm.c b/hw/misc/imx_ccm.c
index 427ce5cd1d..863c219e7c 100644
--- a/hw/misc/imx_ccm.c
+++ b/hw/misc/imx_ccm.c
@@ -281,7 +281,7 @@ static int imx_ccm_init(SysBusDevice *dev)
 {
     IMXCCMState *s = FROM_SYSBUS(typeof(*s), dev);
 
-    memory_region_init_io(&s->iomem, &imx_ccm_ops, s, "imx_ccm", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &imx_ccm_ops, s, "imx_ccm", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
     return 0;
diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index 5658f733f4..522740d5bb 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -339,7 +339,7 @@ static void create_shared_memory_BAR(IVShmemState *s, int fd) {
 
     ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
 
-    memory_region_init_ram_ptr(&s->ivshmem, "ivshmem.bar2",
+    memory_region_init_ram_ptr(&s->ivshmem, NULL, "ivshmem.bar2",
                                s->ivshmem_size, ptr);
     vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
     memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
@@ -467,7 +467,7 @@ static void ivshmem_read(void *opaque, const uint8_t * buf, int flags)
         /* mmap the region and map into the BAR2 */
         map_ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED,
                                                             incoming_fd, 0);
-        memory_region_init_ram_ptr(&s->ivshmem,
+        memory_region_init_ram_ptr(&s->ivshmem, NULL,
                                    "ivshmem.bar2", s->ivshmem_size, map_ptr);
         vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
 
@@ -685,14 +685,14 @@ static int pci_ivshmem_init(PCIDevice *dev)
 
     s->shm_fd = 0;
 
-    memory_region_init_io(&s->ivshmem_mmio, &ivshmem_mmio_ops, s,
+    memory_region_init_io(&s->ivshmem_mmio, NULL, &ivshmem_mmio_ops, s,
                           "ivshmem-mmio", IVSHMEM_REG_BAR_SIZE);
 
     /* region for registers*/
     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
                      &s->ivshmem_mmio);
 
-    memory_region_init(&s->bar, "ivshmem-bar2-container", s->ivshmem_size);
+    memory_region_init(&s->bar, NULL, "ivshmem-bar2-container", s->ivshmem_size);
     s->ivshmem_attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
         PCI_BASE_ADDRESS_MEM_PREFETCH;
     if (s->ivshmem_64bit) {
diff --git a/hw/misc/lm32_sys.c b/hw/misc/lm32_sys.c
index aeaf2b7b7b..accfbe3c44 100644
--- a/hw/misc/lm32_sys.c
+++ b/hw/misc/lm32_sys.c
@@ -117,7 +117,7 @@ static int lm32_sys_init(SysBusDevice *dev)
 {
     LM32SysState *s = FROM_SYSBUS(typeof(*s), dev);
 
-    memory_region_init_io(&s->iomem, &sys_ops , s, "sys", R_MAX * 4);
+    memory_region_init_io(&s->iomem, NULL, &sys_ops , s, "sys", R_MAX * 4);
     sysbus_init_mmio(dev, &s->iomem);
 
     /* Note: This device is not created in the board initialization,
diff --git a/hw/misc/macio/cuda.c b/hw/misc/macio/cuda.c
index f797796a36..c0fd7da118 100644
--- a/hw/misc/macio/cuda.c
+++ b/hw/misc/macio/cuda.c
@@ -703,7 +703,7 @@ static void cuda_initfn(Object *obj)
     CUDAState *s = CUDA(obj);
     int i;
 
-    memory_region_init_io(&s->mem, &cuda_ops, s, "cuda", 0x2000);
+    memory_region_init_io(&s->mem, NULL, &cuda_ops, s, "cuda", 0x2000);
     sysbus_init_mmio(d, &s->mem);
     sysbus_init_irq(d, &s->irq);
 
diff --git a/hw/misc/macio/mac_dbdma.c b/hw/misc/macio/mac_dbdma.c
index 2fc7f87bb6..a1d7862a66 100644
--- a/hw/misc/macio/mac_dbdma.c
+++ b/hw/misc/macio/mac_dbdma.c
@@ -848,7 +848,7 @@ void* DBDMA_init (MemoryRegion **dbdma_mem)
 
     s = g_malloc0(sizeof(DBDMAState));
 
-    memory_region_init_io(&s->mem, &dbdma_ops, s, "dbdma", 0x1000);
+    memory_region_init_io(&s->mem, NULL, &dbdma_ops, s, "dbdma", 0x1000);
     *dbdma_mem = &s->mem;
     vmstate_register(NULL, -1, &vmstate_dbdma, s);
     qemu_register_reset(dbdma_reset, s);
diff --git a/hw/misc/macio/macio.c b/hw/misc/macio/macio.c
index fd4c8e5f99..76a1cfba32 100644
--- a/hw/misc/macio/macio.c
+++ b/hw/misc/macio/macio.c
@@ -104,11 +104,11 @@ static void macio_escc_legacy_setup(MacIOState *macio_state)
         0xF0, 0xE0,
     };
 
-    memory_region_init(escc_legacy, "escc-legacy", 256);
+    memory_region_init(escc_legacy, NULL, "escc-legacy", 256);
     for (i = 0; i < ARRAY_SIZE(maps); i += 2) {
         MemoryRegion *port = g_new(MemoryRegion, 1);
-        memory_region_init_alias(port, "escc-legacy-port", macio_state->escc_mem,
-                                 maps[i+1], 0x2);
+        memory_region_init_alias(port, NULL, "escc-legacy-port",
+                                 macio_state->escc_mem, maps[i+1], 0x2);
         memory_region_add_subregion(escc_legacy, maps[i], port);
     }
 
@@ -269,7 +269,7 @@ static void macio_instance_init(Object *obj)
     MacIOState *s = MACIO(obj);
     MemoryRegion *dbdma_mem;
 
-    memory_region_init(&s->bar, "macio", 0x80000);
+    memory_region_init(&s->bar, NULL, "macio", 0x80000);
 
     object_initialize(&s->cuda, TYPE_CUDA);
     qdev_set_parent_bus(DEVICE(&s->cuda), sysbus_get_default());
diff --git a/hw/misc/milkymist-hpdmc.c b/hw/misc/milkymist-hpdmc.c
index d922f6ffad..f4826b94bb 100644
--- a/hw/misc/milkymist-hpdmc.c
+++ b/hw/misc/milkymist-hpdmc.c
@@ -127,7 +127,7 @@ static int milkymist_hpdmc_init(SysBusDevice *dev)
 {
     MilkymistHpdmcState *s = FROM_SYSBUS(typeof(*s), dev);
 
-    memory_region_init_io(&s->regs_region, &hpdmc_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &hpdmc_mmio_ops, s,
             "milkymist-hpdmc", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/misc/milkymist-pfpu.c b/hw/misc/milkymist-pfpu.c
index fe1b039550..0051bc955b 100644
--- a/hw/misc/milkymist-pfpu.c
+++ b/hw/misc/milkymist-pfpu.c
@@ -497,7 +497,7 @@ static int milkymist_pfpu_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->regs_region, &pfpu_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &pfpu_mmio_ops, s,
             "milkymist-pfpu", MICROCODE_END * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/misc/mst_fpga.c b/hw/misc/mst_fpga.c
index 1dd15054d0..b727dabfbf 100644
--- a/hw/misc/mst_fpga.c
+++ b/hw/misc/mst_fpga.c
@@ -208,7 +208,7 @@ static int mst_fpga_init(SysBusDevice *dev)
 	/* alloc the external 16 irqs */
 	qdev_init_gpio_in(&dev->qdev, mst_fpga_set_irq, MST_NUM_IRQS);
 
-	memory_region_init_io(&s->iomem, &mst_fpga_ops, s,
+	memory_region_init_io(&s->iomem, NULL, &mst_fpga_ops, s,
 			    "fpga", 0x00100000);
 	sysbus_init_mmio(dev, &s->iomem);
 	return 0;
diff --git a/hw/misc/omap_gpmc.c b/hw/misc/omap_gpmc.c
index 91adb66c2b..2047274123 100644
--- a/hw/misc/omap_gpmc.c
+++ b/hw/misc/omap_gpmc.c
@@ -413,7 +413,7 @@ static void omap_gpmc_cs_map(struct omap_gpmc_s *s, int cs)
      * constant), the mask should cause wrapping of the address space, so
      * that the same memory becomes accessible at every <i>size</i> bytes
      * starting from <i>base</i>.  */
-    memory_region_init(&f->container, "omap-gpmc-file", size);
+    memory_region_init(&f->container, NULL, "omap-gpmc-file", size);
     memory_region_add_subregion(&f->container, 0,
                                 omap_gpmc_cs_memregion(s, cs));
     memory_region_add_subregion(get_system_memory(), base,
@@ -826,7 +826,7 @@ struct omap_gpmc_s *omap_gpmc_init(struct omap_mpu_state_s *mpu,
     struct omap_gpmc_s *s = (struct omap_gpmc_s *)
             g_malloc0(sizeof(struct omap_gpmc_s));
 
-    memory_region_init_io(&s->iomem, &omap_gpmc_ops, s, "omap-gpmc", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &omap_gpmc_ops, s, "omap-gpmc", 0x1000);
     memory_region_add_subregion(get_system_memory(), base, &s->iomem);
 
     s->irq = irq;
@@ -843,14 +843,14 @@ struct omap_gpmc_s *omap_gpmc_init(struct omap_mpu_state_s *mpu,
      * guest-requested size.
      */
     for (cs = 0; cs < 8; cs++) {
-        memory_region_init_io(&s->cs_file[cs].nandiomem,
+        memory_region_init_io(&s->cs_file[cs].nandiomem, NULL,
                               &omap_nand_ops,
                               &s->cs_file[cs],
                               "omap-nand",
                               256 * 1024 * 1024);
     }
 
-    memory_region_init_io(&s->prefetch.iomem, &omap_prefetch_ops, s,
+    memory_region_init_io(&s->prefetch.iomem, NULL, &omap_prefetch_ops, s,
                           "omap-gpmc-prefetch", 256 * 1024 * 1024);
     return s;
 }
diff --git a/hw/misc/omap_l4.c b/hw/misc/omap_l4.c
index ac8251f736..f2372500c0 100644
--- a/hw/misc/omap_l4.c
+++ b/hw/misc/omap_l4.c
@@ -136,7 +136,7 @@ struct omap_target_agent_s *omap_l4ta_get(struct omap_l4_s *bus,
     ta->status = 0x00000000;
     ta->control = 0x00000200;	/* XXX 01000200 for L4TAO */
 
-    memory_region_init_io(&ta->iomem, &omap_l4ta_ops, ta, "omap.l4ta",
+    memory_region_init_io(&ta->iomem, NULL, &omap_l4ta_ops, ta, "omap.l4ta",
                           omap_l4_region_size(ta, info->ta_region));
     omap_l4_attach(ta, info->ta_region, &ta->iomem);
 
diff --git a/hw/misc/omap_sdrc.c b/hw/misc/omap_sdrc.c
index e38b571054..ed62caf03f 100644
--- a/hw/misc/omap_sdrc.c
+++ b/hw/misc/omap_sdrc.c
@@ -161,7 +161,7 @@ struct omap_sdrc_s *omap_sdrc_init(MemoryRegion *sysmem,
 
     omap_sdrc_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_sdrc_ops, s, "omap.sdrc", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &omap_sdrc_ops, s, "omap.sdrc", 0x1000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     return s;
diff --git a/hw/misc/omap_tap.c b/hw/misc/omap_tap.c
index 99b70d5a75..9d2b71014c 100644
--- a/hw/misc/omap_tap.c
+++ b/hw/misc/omap_tap.c
@@ -110,7 +110,7 @@ static const MemoryRegionOps omap_tap_ops = {
 void omap_tap_init(struct omap_target_agent_s *ta,
                 struct omap_mpu_state_s *mpu)
 {
-    memory_region_init_io(&mpu->tap_iomem, &omap_tap_ops, mpu, "omap.tap",
+    memory_region_init_io(&mpu->tap_iomem, NULL, &omap_tap_ops, mpu, "omap.tap",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &mpu->tap_iomem);
 }
diff --git a/hw/misc/pc-testdev.c b/hw/misc/pc-testdev.c
index e6707d69d4..31c9878649 100644
--- a/hw/misc/pc-testdev.c
+++ b/hw/misc/pc-testdev.c
@@ -149,13 +149,13 @@ static void testdev_realizefn(DeviceState *d, Error **errp)
     MemoryRegion *mem = isa_address_space(isa);
     MemoryRegion *io = isa_address_space_io(isa);
 
-    memory_region_init_io(&dev->ioport, &test_ioport_ops, dev,
+    memory_region_init_io(&dev->ioport, NULL, &test_ioport_ops, dev,
                           "pc-testdev-ioport", 4);
-    memory_region_init_io(&dev->flush, &test_flush_ops, dev,
+    memory_region_init_io(&dev->flush, NULL, &test_flush_ops, dev,
                           "pc-testdev-flush-page", 4);
-    memory_region_init_io(&dev->irq, &test_irq_ops, dev,
+    memory_region_init_io(&dev->irq, NULL, &test_irq_ops, dev,
                           "pc-testdev-irq-line", 24);
-    memory_region_init_io(&dev->iomem, &test_iomem_ops, dev,
+    memory_region_init_io(&dev->iomem, NULL, &test_iomem_ops, dev,
                           "pc-testdev-iomem", IOMEM_LEN);
 
     memory_region_add_subregion(io,  0xe0,       &dev->ioport);
diff --git a/hw/misc/pci-testdev.c b/hw/misc/pci-testdev.c
index 71ce5a3e08..fb9a58c5a3 100644
--- a/hw/misc/pci-testdev.c
+++ b/hw/misc/pci-testdev.c
@@ -236,9 +236,9 @@ static int pci_testdev_init(PCIDevice *pci_dev)
 
     pci_conf[PCI_INTERRUPT_PIN] = 0; /* no interrupt pin */
 
-    memory_region_init_io(&d->mmio, &pci_testdev_mmio_ops, d,
+    memory_region_init_io(&d->mmio, NULL, &pci_testdev_mmio_ops, d,
                           "pci-testdev-mmio", IOTEST_MEMSIZE * 2);
-    memory_region_init_io(&d->portio, &pci_testdev_pio_ops, d,
+    memory_region_init_io(&d->portio, NULL, &pci_testdev_pio_ops, d,
                           "pci-testdev-portio", IOTEST_IOSIZE * 2);
     pci_register_bar(&d->dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &d->mmio);
     pci_register_bar(&d->dev, 1, PCI_BASE_ADDRESS_SPACE_IO, &d->portio);
diff --git a/hw/misc/puv3_pm.c b/hw/misc/puv3_pm.c
index 0aacdc2fce..d4a863f0c9 100644
--- a/hw/misc/puv3_pm.c
+++ b/hw/misc/puv3_pm.c
@@ -120,7 +120,7 @@ static int puv3_pm_init(SysBusDevice *dev)
 
     s->reg_PCGR = 0x0;
 
-    memory_region_init_io(&s->iomem, &puv3_pm_ops, s, "puv3_pm",
+    memory_region_init_io(&s->iomem, NULL, &puv3_pm_ops, s, "puv3_pm",
             PUV3_REGS_OFFSET);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/misc/pvpanic.c b/hw/misc/pvpanic.c
index 060099b553..00d6e6343f 100644
--- a/hw/misc/pvpanic.c
+++ b/hw/misc/pvpanic.c
@@ -90,7 +90,7 @@ static void pvpanic_isa_initfn(Object *obj)
 {
     PVPanicState *s = ISA_PVPANIC_DEVICE(obj);
 
-    memory_region_init_io(&s->io, &pvpanic_ops, s, "pvpanic", 1);
+    memory_region_init_io(&s->io, NULL, &pvpanic_ops, s, "pvpanic", 1);
 }
 
 static void pvpanic_isa_realizefn(DeviceState *dev, Error **errp)
diff --git a/hw/misc/pxa2xx_pcmcia.c b/hw/misc/pxa2xx_pcmcia.c
index 323d458491..ef71a2af74 100644
--- a/hw/misc/pxa2xx_pcmcia.c
+++ b/hw/misc/pxa2xx_pcmcia.c
@@ -128,7 +128,7 @@ PXA2xxPCMCIAState *pxa2xx_pcmcia_init(MemoryRegion *sysmem,
             g_malloc0(sizeof(PXA2xxPCMCIAState));
 
     /* Socket I/O Memory Space */
-    memory_region_init_io(&s->iomem, &pxa2xx_pcmcia_io_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_pcmcia_io_ops, s,
                           "pxa2xx-pcmcia-io", 0x04000000);
     memory_region_add_subregion(sysmem, base | 0x00000000,
                                 &s->iomem);
@@ -136,13 +136,13 @@ PXA2xxPCMCIAState *pxa2xx_pcmcia_init(MemoryRegion *sysmem,
     /* Then next 64 MB is reserved */
 
     /* Socket Attribute Memory Space */
-    memory_region_init_io(&s->attr_iomem, &pxa2xx_pcmcia_attr_ops, s,
+    memory_region_init_io(&s->attr_iomem, NULL, &pxa2xx_pcmcia_attr_ops, s,
                           "pxa2xx-pcmcia-attribute", 0x04000000);
     memory_region_add_subregion(sysmem, base | 0x08000000,
                                 &s->attr_iomem);
 
     /* Socket Common Memory Space */
-    memory_region_init_io(&s->common_iomem, &pxa2xx_pcmcia_common_ops, s,
+    memory_region_init_io(&s->common_iomem, NULL, &pxa2xx_pcmcia_common_ops, s,
                           "pxa2xx-pcmcia-common", 0x04000000);
     memory_region_add_subregion(sysmem, base | 0x0c000000,
                                 &s->common_iomem);
diff --git a/hw/misc/slavio_misc.c b/hw/misc/slavio_misc.c
index a7a9368864..dbc6081b1d 100644
--- a/hw/misc/slavio_misc.c
+++ b/hw/misc/slavio_misc.c
@@ -412,7 +412,7 @@ static int apc_init1(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->cpu_halt);
 
     /* Power management (APC) XXX: not a Slavio device */
-    memory_region_init_io(&s->iomem, &apc_mem_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &apc_mem_ops, s,
                           "apc", MISC_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
@@ -427,39 +427,39 @@ static int slavio_misc_init1(SysBusDevice *dev)
 
     /* 8 bit registers */
     /* Slavio control */
-    memory_region_init_io(&s->cfg_iomem, &slavio_cfg_mem_ops, s,
+    memory_region_init_io(&s->cfg_iomem, NULL, &slavio_cfg_mem_ops, s,
                           "configuration", MISC_SIZE);
     sysbus_init_mmio(dev, &s->cfg_iomem);
 
     /* Diagnostics */
-    memory_region_init_io(&s->diag_iomem, &slavio_diag_mem_ops, s,
+    memory_region_init_io(&s->diag_iomem, NULL, &slavio_diag_mem_ops, s,
                           "diagnostic", MISC_SIZE);
     sysbus_init_mmio(dev, &s->diag_iomem);
 
     /* Modem control */
-    memory_region_init_io(&s->mdm_iomem, &slavio_mdm_mem_ops, s,
+    memory_region_init_io(&s->mdm_iomem, NULL, &slavio_mdm_mem_ops, s,
                           "modem", MISC_SIZE);
     sysbus_init_mmio(dev, &s->mdm_iomem);
 
     /* 16 bit registers */
     /* ss600mp diag LEDs */
-    memory_region_init_io(&s->led_iomem, &slavio_led_mem_ops, s,
+    memory_region_init_io(&s->led_iomem, NULL, &slavio_led_mem_ops, s,
                           "leds", MISC_SIZE);
     sysbus_init_mmio(dev, &s->led_iomem);
 
     /* 32 bit registers */
     /* System control */
-    memory_region_init_io(&s->sysctrl_iomem, &slavio_sysctrl_mem_ops, s,
+    memory_region_init_io(&s->sysctrl_iomem, NULL, &slavio_sysctrl_mem_ops, s,
                           "system-control", MISC_SIZE);
     sysbus_init_mmio(dev, &s->sysctrl_iomem);
 
     /* AUX 1 (Misc System Functions) */
-    memory_region_init_io(&s->aux1_iomem, &slavio_aux1_mem_ops, s,
+    memory_region_init_io(&s->aux1_iomem, NULL, &slavio_aux1_mem_ops, s,
                           "misc-system-functions", MISC_SIZE);
     sysbus_init_mmio(dev, &s->aux1_iomem);
 
     /* AUX 2 (Software Powerdown Control) */
-    memory_region_init_io(&s->aux2_iomem, &slavio_aux2_mem_ops, s,
+    memory_region_init_io(&s->aux2_iomem, NULL, &slavio_aux2_mem_ops, s,
                           "software-powerdown-control", MISC_SIZE);
     sysbus_init_mmio(dev, &s->aux2_iomem);
 
diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
index 52fb03601d..e2e957d6f6 100644
--- a/hw/misc/vfio.c
+++ b/hw/misc/vfio.c
@@ -1154,7 +1154,7 @@ static void vfio_vga_probe_ati_3c3_quirk(VFIODevice *vdev)
     quirk->vdev = vdev;
     quirk->data = (physbar >> 8) & 0xff;
 
-    memory_region_init_io(&quirk->mem, &vfio_ati_3c3_quirk, quirk,
+    memory_region_init_io(&quirk->mem, NULL, &vfio_ati_3c3_quirk, quirk,
                           "vfio-ati-3c3-quirk", 1);
     memory_region_add_subregion(&vdev->vga.region[QEMU_PCI_VGA_IO_HI].mem, 3,
                                 &quirk->mem);
@@ -1245,7 +1245,7 @@ static void vfio_probe_ati_4010_quirk(VFIODevice *vdev, int nr)
     quirk = g_malloc0(sizeof(*quirk));
     quirk->vdev = vdev;
 
-    memory_region_init_io(&quirk->mem, &vfio_ati_4010_quirk, quirk,
+    memory_region_init_io(&quirk->mem, NULL, &vfio_ati_4010_quirk, quirk,
                           "vfio-ati-4010-quirk", 8);
     memory_region_add_subregion_overlap(&vdev->bars[nr].mem, 0, &quirk->mem, 1);
 
@@ -1331,7 +1331,7 @@ static void vfio_probe_ati_f10_quirk(VFIODevice *vdev, int nr)
     quirk = g_malloc0(sizeof(*quirk));
     quirk->vdev = vdev;
 
-    memory_region_init_io(&quirk->mem, &vfio_ati_f10_quirk, quirk,
+    memory_region_init_io(&quirk->mem, NULL, &vfio_ati_f10_quirk, quirk,
                           "vfio-ati-f10-quirk", 8);
     memory_region_add_subregion_overlap(&vdev->bars[nr].mem, 0, &quirk->mem, 1);
 
@@ -1451,7 +1451,7 @@ static void vfio_vga_probe_nvidia_3d0_quirk(VFIODevice *vdev)
     quirk = g_malloc0(sizeof(*quirk));
     quirk->vdev = vdev;
 
-    memory_region_init_io(&quirk->mem, &vfio_nvidia_3d0_quirk, quirk,
+    memory_region_init_io(&quirk->mem, NULL, &vfio_nvidia_3d0_quirk, quirk,
                           "vfio-nvidia-3d0-quirk", 6);
     memory_region_add_subregion(&vdev->vga.region[QEMU_PCI_VGA_IO_HI].mem,
                                 0x10, &quirk->mem);
@@ -1566,7 +1566,7 @@ static void vfio_probe_nvidia_bar5_window_quirk(VFIODevice *vdev, int nr)
     quirk = g_malloc0(sizeof(*quirk));
     quirk->vdev = vdev;
 
-    memory_region_init_io(&quirk->mem, &vfio_nvidia_bar5_window_quirk, quirk,
+    memory_region_init_io(&quirk->mem, NULL, &vfio_nvidia_bar5_window_quirk, quirk,
                           "vfio-nvidia-bar5-window-quirk", 16);
     memory_region_add_subregion_overlap(&vdev->bars[nr].mem, 0, &quirk->mem, 1);
 
@@ -1644,7 +1644,7 @@ static void vfio_probe_nvidia_bar0_88000_quirk(VFIODevice *vdev, int nr)
     quirk = g_malloc0(sizeof(*quirk));
     quirk->vdev = vdev;
 
-    memory_region_init_io(&quirk->mem, &vfio_nvidia_bar0_88000_quirk, quirk,
+    memory_region_init_io(&quirk->mem, NULL, &vfio_nvidia_bar0_88000_quirk, quirk,
                           "vfio-nvidia-bar0-88000-quirk",
                           TARGET_PAGE_ALIGN(PCIE_CONFIG_SPACE_SIZE));
     memory_region_add_subregion_overlap(&vdev->bars[nr].mem,
@@ -1723,7 +1723,7 @@ static void vfio_probe_nvidia_bar0_1800_quirk(VFIODevice *vdev, int nr)
     quirk = g_malloc0(sizeof(*quirk));
     quirk->vdev = vdev;
 
-    memory_region_init_io(&quirk->mem, &vfio_nvidia_bar0_1800_quirk, quirk,
+    memory_region_init_io(&quirk->mem, NULL, &vfio_nvidia_bar0_1800_quirk, quirk,
                           "vfio-nvidia-bar0-1800-quirk",
                           TARGET_PAGE_ALIGN(PCI_CONFIG_SPACE_SIZE));
     memory_region_add_subregion_overlap(&vdev->bars[nr].mem,
@@ -2228,11 +2228,11 @@ static int vfio_mmap_bar(VFIOBAR *bar, MemoryRegion *mem, MemoryRegion *submem,
             goto empty_region;
         }
 
-        memory_region_init_ram_ptr(submem, name, size, *map);
+        memory_region_init_ram_ptr(submem, NULL, name, size, *map);
     } else {
 empty_region:
         /* Create a zero sized sub-region to make cleanup easy. */
-        memory_region_init(submem, name, 0);
+        memory_region_init(submem, NULL, name, 0);
     }
 
     memory_region_add_subregion(mem, offset, submem);
@@ -2271,7 +2271,7 @@ static void vfio_map_bar(VFIODevice *vdev, int nr)
            ~PCI_BASE_ADDRESS_IO_MASK : ~PCI_BASE_ADDRESS_MEM_MASK);
 
     /* A "slow" read/write mapping underlies all BARs */
-    memory_region_init_io(&bar->mem, &vfio_bar_ops, bar, name, size);
+    memory_region_init_io(&bar->mem, NULL, &vfio_bar_ops, bar, name, size);
     pci_register_bar(&vdev->pdev, nr, type, &bar->mem);
 
     /*
@@ -2315,17 +2315,17 @@ static void vfio_map_bars(VFIODevice *vdev)
     }
 
     if (vdev->has_vga) {
-        memory_region_init_io(&vdev->vga.region[QEMU_PCI_VGA_MEM].mem,
+        memory_region_init_io(&vdev->vga.region[QEMU_PCI_VGA_MEM].mem, NULL,
                               &vfio_vga_ops,
                               &vdev->vga.region[QEMU_PCI_VGA_MEM],
                               "vfio-vga-mmio@0xa0000",
                               QEMU_PCI_VGA_MEM_SIZE);
-        memory_region_init_io(&vdev->vga.region[QEMU_PCI_VGA_IO_LO].mem,
+        memory_region_init_io(&vdev->vga.region[QEMU_PCI_VGA_IO_LO].mem, NULL,
                               &vfio_vga_ops,
                               &vdev->vga.region[QEMU_PCI_VGA_IO_LO],
                               "vfio-vga-io@0x3b0",
                               QEMU_PCI_VGA_IO_LO_SIZE);
-        memory_region_init_io(&vdev->vga.region[QEMU_PCI_VGA_IO_HI].mem,
+        memory_region_init_io(&vdev->vga.region[QEMU_PCI_VGA_IO_HI].mem, NULL,
                               &vfio_vga_ops,
                               &vdev->vga.region[QEMU_PCI_VGA_IO_HI],
                               "vfio-vga-io@0x3c0",
@@ -2588,7 +2588,7 @@ static int vfio_load_rom(VFIODevice *vdev)
     snprintf(name, sizeof(name), "vfio[%04x:%02x:%02x.%x].rom",
              vdev->host.domain, vdev->host.bus, vdev->host.slot,
              vdev->host.function);
-    memory_region_init_ram(&vdev->pdev.rom, name, size);
+    memory_region_init_ram(&vdev->pdev.rom, NULL, name, size);
     ptr = memory_region_get_ram_ptr(&vdev->pdev.rom);
     memset(ptr, 0xff, size);
 
diff --git a/hw/misc/vmport.c b/hw/misc/vmport.c
index 86390728f5..7f64ccda62 100644
--- a/hw/misc/vmport.c
+++ b/hw/misc/vmport.c
@@ -142,7 +142,7 @@ static void vmport_realizefn(DeviceState *dev, Error **errp)
     ISADevice *isadev = ISA_DEVICE(dev);
     VMPortState *s = VMPORT(dev);
 
-    memory_region_init_io(&s->io, &vmport_ops, s, "vmport", 1);
+    memory_region_init_io(&s->io, NULL, &vmport_ops, s, "vmport", 1);
     isa_register_ioport(isadev, &s->io, 0x5658);
 
     port_state = s;
diff --git a/hw/misc/zynq_slcr.c b/hw/misc/zynq_slcr.c
index 8418327261..d7c2d190ec 100644
--- a/hw/misc/zynq_slcr.c
+++ b/hw/misc/zynq_slcr.c
@@ -494,7 +494,7 @@ static int zynq_slcr_init(SysBusDevice *dev)
 {
     ZynqSLCRState *s = FROM_SYSBUS(ZynqSLCRState, dev);
 
-    memory_region_init_io(&s->iomem, &slcr_ops, s, "slcr", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &slcr_ops, s, "slcr", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
     return 0;
diff --git a/hw/moxie/moxiesim.c b/hw/moxie/moxiesim.c
index 649f9a7daa..ef4f3a84d7 100644
--- a/hw/moxie/moxiesim.c
+++ b/hw/moxie/moxiesim.c
@@ -136,11 +136,11 @@ static void moxiesim_init(QEMUMachineInitArgs *args)
     qemu_register_reset(main_cpu_reset, cpu);
 
     /* Allocate RAM. */
-    memory_region_init_ram(ram, "moxiesim.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "moxiesim.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, ram_base, ram);
 
-    memory_region_init_ram(rom, "moxie.rom", 128*0x1000);
+    memory_region_init_ram(rom, NULL, "moxie.rom", 128*0x1000);
     vmstate_register_ram_global(rom);
     memory_region_add_subregion(get_system_memory(), 0x1000, rom);
 
diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c
index e177057e49..c94d3e746d 100644
--- a/hw/net/cadence_gem.c
+++ b/hw/net/cadence_gem.c
@@ -1163,7 +1163,7 @@ static int gem_init(SysBusDevice *dev)
 
     s = FROM_SYSBUS(GemState, dev);
     gem_init_register_masks(s);
-    memory_region_init_io(&s->iomem, &gem_ops, s, "enet", sizeof(s->regs));
+    memory_region_init_io(&s->iomem, NULL, &gem_ops, s, "enet", sizeof(s->regs));
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     qemu_macaddr_default_if_unset(&s->conf.macaddr);
diff --git a/hw/net/dp8393x.c b/hw/net/dp8393x.c
index 2289f089ad..049aa704c1 100644
--- a/hw/net/dp8393x.c
+++ b/hw/net/dp8393x.c
@@ -908,7 +908,7 @@ void dp83932_init(NICInfo *nd, hwaddr base, int it_shift,
     qemu_register_reset(nic_reset, s);
     nic_reset(s);
 
-    memory_region_init_io(&s->mmio, &dp8393x_ops, s,
+    memory_region_init_io(&s->mmio, NULL, &dp8393x_ops, s,
                           "dp8393x", 0x40 << it_shift);
     memory_region_add_subregion(address_space, base, &s->mmio);
 }
diff --git a/hw/net/e1000.c b/hw/net/e1000.c
index e6f46f0c51..e5c0978d5d 100644
--- a/hw/net/e1000.c
+++ b/hw/net/e1000.c
@@ -1276,13 +1276,13 @@ e1000_mmio_setup(E1000State *d)
         E1000_IMC, E1000_TCTL, E1000_TDT, PNPMMIO_SIZE
     };
 
-    memory_region_init_io(&d->mmio, &e1000_mmio_ops, d, "e1000-mmio",
+    memory_region_init_io(&d->mmio, NULL, &e1000_mmio_ops, d, "e1000-mmio",
                           PNPMMIO_SIZE);
     memory_region_add_coalescing(&d->mmio, 0, excluded_regs[0]);
     for (i = 0; excluded_regs[i] != PNPMMIO_SIZE; i++)
         memory_region_add_coalescing(&d->mmio, excluded_regs[i] + 4,
                                      excluded_regs[i+1] - excluded_regs[i] - 4);
-    memory_region_init_io(&d->io, &e1000_io_ops, d, "e1000-io", IOPORT_SIZE);
+    memory_region_init_io(&d->io, NULL, &e1000_io_ops, d, "e1000-io", IOPORT_SIZE);
 }
 
 static void
diff --git a/hw/net/eepro100.c b/hw/net/eepro100.c
index dc99ea6ea0..abfcdbd493 100644
--- a/hw/net/eepro100.c
+++ b/hw/net/eepro100.c
@@ -1876,14 +1876,14 @@ static int e100_nic_init(PCIDevice *pci_dev)
     s->eeprom = eeprom93xx_new(&pci_dev->qdev, EEPROM_SIZE);
 
     /* Handler for memory-mapped I/O */
-    memory_region_init_io(&s->mmio_bar, &eepro100_ops, s, "eepro100-mmio",
+    memory_region_init_io(&s->mmio_bar, NULL, &eepro100_ops, s, "eepro100-mmio",
                           PCI_MEM_SIZE);
     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_MEM_PREFETCH, &s->mmio_bar);
-    memory_region_init_io(&s->io_bar, &eepro100_ops, s, "eepro100-io",
+    memory_region_init_io(&s->io_bar, NULL, &eepro100_ops, s, "eepro100-io",
                           PCI_IO_SIZE);
     pci_register_bar(&s->dev, 1, PCI_BASE_ADDRESS_SPACE_IO, &s->io_bar);
     /* FIXME: flash aliases to mmio?! */
-    memory_region_init_io(&s->flash_bar, &eepro100_ops, s, "eepro100-flash",
+    memory_region_init_io(&s->flash_bar, NULL, &eepro100_ops, s, "eepro100-flash",
                           PCI_FLASH_SIZE);
     pci_register_bar(&s->dev, 2, 0, &s->flash_bar);
 
diff --git a/hw/net/etraxfs_eth.c b/hw/net/etraxfs_eth.c
index 1039913e0f..2ade0c0dd6 100644
--- a/hw/net/etraxfs_eth.c
+++ b/hw/net/etraxfs_eth.c
@@ -610,7 +610,7 @@ static int fs_eth_init(SysBusDevice *dev)
     s->dma_in->client.opaque = s;
     s->dma_in->client.pull = NULL;
 
-    memory_region_init_io(&s->mmio, &eth_ops, s, "etraxfs-eth", 0x5c);
+    memory_region_init_io(&s->mmio, NULL, &eth_ops, s, "etraxfs-eth", 0x5c);
     sysbus_init_mmio(dev, &s->mmio);
 
     qemu_macaddr_default_if_unset(&s->conf.macaddr);
diff --git a/hw/net/lan9118.c b/hw/net/lan9118.c
index 403fb868ae..ce68399116 100644
--- a/hw/net/lan9118.c
+++ b/hw/net/lan9118.c
@@ -1328,7 +1328,7 @@ static int lan9118_init1(SysBusDevice *dev)
     const MemoryRegionOps *mem_ops =
             s->mode_16bit ? &lan9118_16bit_mem_ops : &lan9118_mem_ops;
 
-    memory_region_init_io(&s->mmio, mem_ops, s, "lan9118-mmio", 0x100);
+    memory_region_init_io(&s->mmio, NULL, mem_ops, s, "lan9118-mmio", 0x100);
     sysbus_init_mmio(dev, &s->mmio);
     sysbus_init_irq(dev, &s->irq);
     qemu_macaddr_default_if_unset(&s->conf.macaddr);
diff --git a/hw/net/lance.c b/hw/net/lance.c
index 187497c0ce..1d3999d832 100644
--- a/hw/net/lance.c
+++ b/hw/net/lance.c
@@ -117,7 +117,7 @@ static int lance_init(SysBusDevice *dev)
     SysBusPCNetState *d = FROM_SYSBUS(SysBusPCNetState, dev);
     PCNetState *s = &d->state;
 
-    memory_region_init_io(&s->mmio, &lance_mem_ops, d, "lance-mmio", 4);
+    memory_region_init_io(&s->mmio, NULL, &lance_mem_ops, d, "lance-mmio", 4);
 
     qdev_init_gpio_in(&dev->qdev, parent_lance_reset, 1);
 
diff --git a/hw/net/mcf_fec.c b/hw/net/mcf_fec.c
index 2ef5a0d73d..4bff3de34f 100644
--- a/hw/net/mcf_fec.c
+++ b/hw/net/mcf_fec.c
@@ -468,7 +468,7 @@ void mcf_fec_init(MemoryRegion *sysmem, NICInfo *nd,
     s->sysmem = sysmem;
     s->irq = irq;
 
-    memory_region_init_io(&s->iomem, &mcf_fec_ops, s, "fec", 0x400);
+    memory_region_init_io(&s->iomem, NULL, &mcf_fec_ops, s, "fec", 0x400);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     s->conf.macaddr = nd->macaddr;
diff --git a/hw/net/milkymist-minimac2.c b/hw/net/milkymist-minimac2.c
index 4ef6318418..73fe307d72 100644
--- a/hw/net/milkymist-minimac2.c
+++ b/hw/net/milkymist-minimac2.c
@@ -461,12 +461,12 @@ static int milkymist_minimac2_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->rx_irq);
     sysbus_init_irq(dev, &s->tx_irq);
 
-    memory_region_init_io(&s->regs_region, &minimac2_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &minimac2_ops, s,
                           "milkymist-minimac2", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
     /* register buffers memory */
-    memory_region_init_ram(&s->buffers, "milkymist-minimac2.buffers",
+    memory_region_init_ram(&s->buffers, NULL, "milkymist-minimac2.buffers",
                            buffers_size);
     vmstate_register_ram_global(&s->buffers);
     s->rx0_buf = memory_region_get_ram_ptr(&s->buffers);
diff --git a/hw/net/mipsnet.c b/hw/net/mipsnet.c
index ac6193a89e..c973a21864 100644
--- a/hw/net/mipsnet.c
+++ b/hw/net/mipsnet.c
@@ -235,7 +235,7 @@ static int mipsnet_sysbus_init(SysBusDevice *dev)
 {
     MIPSnetState *s = DO_UPCAST(MIPSnetState, busdev, dev);
 
-    memory_region_init_io(&s->io, &mipsnet_ioport_ops, s, "mipsnet-io", 36);
+    memory_region_init_io(&s->io, NULL, &mipsnet_ioport_ops, s, "mipsnet-io", 36);
     sysbus_init_mmio(dev, &s->io);
     sysbus_init_irq(dev, &s->irq);
 
diff --git a/hw/net/ne2000.c b/hw/net/ne2000.c
index 33ee03e68e..00940af833 100644
--- a/hw/net/ne2000.c
+++ b/hw/net/ne2000.c
@@ -701,7 +701,7 @@ static const MemoryRegionOps ne2000_ops = {
 
 void ne2000_setup_io(NE2000State *s, unsigned size)
 {
-    memory_region_init_io(&s->io, &ne2000_ops, s, "ne2000", size);
+    memory_region_init_io(&s->io, NULL, &ne2000_ops, s, "ne2000", size);
 }
 
 static void ne2000_cleanup(NetClientState *nc)
diff --git a/hw/net/opencores_eth.c b/hw/net/opencores_eth.c
index be64bf2a68..a1baa3c9bd 100644
--- a/hw/net/opencores_eth.c
+++ b/hw/net/opencores_eth.c
@@ -681,11 +681,11 @@ static int sysbus_open_eth_init(SysBusDevice *dev)
 {
     OpenEthState *s = DO_UPCAST(OpenEthState, dev, dev);
 
-    memory_region_init_io(&s->reg_io, &open_eth_reg_ops, s,
+    memory_region_init_io(&s->reg_io, NULL, &open_eth_reg_ops, s,
             "open_eth.regs", 0x54);
     sysbus_init_mmio(dev, &s->reg_io);
 
-    memory_region_init_io(&s->desc_io, &open_eth_desc_ops, s,
+    memory_region_init_io(&s->desc_io, NULL, &open_eth_desc_ops, s,
             "open_eth.desc", 0x400);
     sysbus_init_mmio(dev, &s->desc_io);
 
diff --git a/hw/net/pcnet-pci.c b/hw/net/pcnet-pci.c
index 9df2b87543..e098bf2031 100644
--- a/hw/net/pcnet-pci.c
+++ b/hw/net/pcnet-pci.c
@@ -315,10 +315,10 @@ static int pci_pcnet_init(PCIDevice *pci_dev)
     pci_conf[PCI_MAX_LAT] = 0xff;
 
     /* Handler for memory-mapped I/O */
-    memory_region_init_io(&d->state.mmio, &pcnet_mmio_ops, s, "pcnet-mmio",
+    memory_region_init_io(&d->state.mmio, NULL, &pcnet_mmio_ops, s, "pcnet-mmio",
                           PCNET_PNPMMIO_SIZE);
 
-    memory_region_init_io(&d->io_bar, &pcnet_io_ops, s, "pcnet-io",
+    memory_region_init_io(&d->io_bar, NULL, &pcnet_io_ops, s, "pcnet-io",
                           PCNET_IOPORT_SIZE);
     pci_register_bar(pci_dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &d->io_bar);
 
diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c
index 7993f9f5b9..a96eb62772 100644
--- a/hw/net/rtl8139.c
+++ b/hw/net/rtl8139.c
@@ -3486,8 +3486,8 @@ static int pci_rtl8139_init(PCIDevice *dev)
      * list bit in status register, and offset 0xdc seems unused. */
     pci_conf[PCI_CAPABILITY_LIST] = 0xdc;
 
-    memory_region_init_io(&s->bar_io, &rtl8139_io_ops, s, "rtl8139", 0x100);
-    memory_region_init_io(&s->bar_mem, &rtl8139_mmio_ops, s, "rtl8139", 0x100);
+    memory_region_init_io(&s->bar_io, NULL, &rtl8139_io_ops, s, "rtl8139", 0x100);
+    memory_region_init_io(&s->bar_mem, NULL, &rtl8139_mmio_ops, s, "rtl8139", 0x100);
     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->bar_io);
     pci_register_bar(&s->dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar_mem);
 
diff --git a/hw/net/smc91c111.c b/hw/net/smc91c111.c
index c2feae6eb8..642970951b 100644
--- a/hw/net/smc91c111.c
+++ b/hw/net/smc91c111.c
@@ -747,7 +747,7 @@ static NetClientInfo net_smc91c111_info = {
 static int smc91c111_init1(SysBusDevice *dev)
 {
     smc91c111_state *s = FROM_SYSBUS(smc91c111_state, dev);
-    memory_region_init_io(&s->mmio, &smc91c111_mem_ops, s,
+    memory_region_init_io(&s->mmio, NULL, &smc91c111_mem_ops, s,
                           "smc91c111-mmio", 16);
     sysbus_init_mmio(dev, &s->mmio);
     sysbus_init_irq(dev, &s->irq);
diff --git a/hw/net/stellaris_enet.c b/hw/net/stellaris_enet.c
index 59b84564a0..b1394a2ff4 100644
--- a/hw/net/stellaris_enet.c
+++ b/hw/net/stellaris_enet.c
@@ -405,7 +405,7 @@ static int stellaris_enet_init(SysBusDevice *dev)
 {
     stellaris_enet_state *s = FROM_SYSBUS(stellaris_enet_state, dev);
 
-    memory_region_init_io(&s->mmio, &stellaris_enet_ops, s, "stellaris_enet",
+    memory_region_init_io(&s->mmio, NULL, &stellaris_enet_ops, s, "stellaris_enet",
                           0x1000);
     sysbus_init_mmio(dev, &s->mmio);
     sysbus_init_irq(dev, &s->irq);
diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c
index 4c575e55a7..23a6b07885 100644
--- a/hw/net/vmxnet3.c
+++ b/hw/net/vmxnet3.c
@@ -2073,17 +2073,17 @@ static int vmxnet3_pci_init(PCIDevice *pci_dev)
 
     VMW_CBPRN("Starting init...");
 
-    memory_region_init_io(&s->bar0, &b0_ops, s,
+    memory_region_init_io(&s->bar0, NULL, &b0_ops, s,
                           "vmxnet3-b0", VMXNET3_PT_REG_SIZE);
     pci_register_bar(pci_dev, VMXNET3_BAR0_IDX,
                      PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar0);
 
-    memory_region_init_io(&s->bar1, &b1_ops, s,
+    memory_region_init_io(&s->bar1, NULL, &b1_ops, s,
                           "vmxnet3-b1", VMXNET3_VD_REG_SIZE);
     pci_register_bar(pci_dev, VMXNET3_BAR1_IDX,
                      PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar1);
 
-    memory_region_init(&s->msix_bar, "vmxnet3-msix-bar",
+    memory_region_init(&s->msix_bar, NULL, "vmxnet3-msix-bar",
                        VMXNET3_MSIX_BAR_SIZE);
     pci_register_bar(pci_dev, VMXNET3_MSIX_BAR_IDX,
                      PCI_BASE_ADDRESS_SPACE_MEMORY, &s->msix_bar);
diff --git a/hw/net/xgmac.c b/hw/net/xgmac.c
index 1d9074a1d0..d334dc593d 100644
--- a/hw/net/xgmac.c
+++ b/hw/net/xgmac.c
@@ -382,7 +382,7 @@ static int xgmac_enet_init(SysBusDevice *dev)
 {
     struct XgmacState *s = FROM_SYSBUS(typeof(*s), dev);
 
-    memory_region_init_io(&s->iomem, &enet_mem_ops, s, "xgmac", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &enet_mem_ops, s, "xgmac", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->sbd_irq);
     sysbus_init_irq(dev, &s->pmt_irq);
diff --git a/hw/net/xilinx_axienet.c b/hw/net/xilinx_axienet.c
index 2ca1511c06..4a4fbd6b97 100644
--- a/hw/net/xilinx_axienet.c
+++ b/hw/net/xilinx_axienet.c
@@ -1001,7 +1001,7 @@ static void xilinx_enet_init(Object *obj)
 
     sysbus_init_irq(sbd, &s->irq);
 
-    memory_region_init_io(&s->iomem, &enet_ops, s, "enet", 0x40000);
+    memory_region_init_io(&s->iomem, NULL, &enet_ops, s, "enet", 0x40000);
     sysbus_init_mmio(sbd, &s->iomem);
 }
 
diff --git a/hw/net/xilinx_ethlite.c b/hw/net/xilinx_ethlite.c
index b2e35237f8..9d7cb8f1de 100644
--- a/hw/net/xilinx_ethlite.c
+++ b/hw/net/xilinx_ethlite.c
@@ -221,7 +221,7 @@ static int xilinx_ethlite_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq);
     s->rxbuf = 0;
 
-    memory_region_init_io(&s->mmio, &eth_ops, s, "xlnx.xps-ethernetlite",
+    memory_region_init_io(&s->mmio, NULL, &eth_ops, s, "xlnx.xps-ethernetlite",
                                                                     R_MAX * 4);
     sysbus_init_mmio(dev, &s->mmio);
 
diff --git a/hw/nvram/ds1225y.c b/hw/nvram/ds1225y.c
index 488f1d7241..1697562d77 100644
--- a/hw/nvram/ds1225y.c
+++ b/hw/nvram/ds1225y.c
@@ -117,7 +117,7 @@ static int nvram_sysbus_initfn(SysBusDevice *dev)
 
     s->contents = g_malloc0(s->chip_size);
 
-    memory_region_init_io(&s->iomem, &nvram_ops, s, "nvram", s->chip_size);
+    memory_region_init_io(&s->iomem, NULL, &nvram_ops, s, "nvram", s->chip_size);
     sysbus_init_mmio(dev, &s->iomem);
 
     /* Read current file */
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 3c255cec01..a37db77f2f 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -526,14 +526,14 @@ static int fw_cfg_init1(SysBusDevice *dev)
 {
     FWCfgState *s = FROM_SYSBUS(FWCfgState, dev);
 
-    memory_region_init_io(&s->ctl_iomem, &fw_cfg_ctl_mem_ops, s,
+    memory_region_init_io(&s->ctl_iomem, NULL, &fw_cfg_ctl_mem_ops, s,
                           "fwcfg.ctl", FW_CFG_SIZE);
     sysbus_init_mmio(dev, &s->ctl_iomem);
-    memory_region_init_io(&s->data_iomem, &fw_cfg_data_mem_ops, s,
+    memory_region_init_io(&s->data_iomem, NULL, &fw_cfg_data_mem_ops, s,
                           "fwcfg.data", FW_CFG_DATA_SIZE);
     sysbus_init_mmio(dev, &s->data_iomem);
     /* In case ctl and data overlap: */
-    memory_region_init_io(&s->comb_iomem, &fw_cfg_comb_mem_ops, s,
+    memory_region_init_io(&s->comb_iomem, NULL, &fw_cfg_comb_mem_ops, s,
                           "fwcfg", FW_CFG_SIZE);
 
     if (s->ctl_iobase + 1 == s->data_iobase) {
diff --git a/hw/nvram/mac_nvram.c b/hw/nvram/mac_nvram.c
index d76a06c486..c91ee5806a 100644
--- a/hw/nvram/mac_nvram.c
+++ b/hw/nvram/mac_nvram.c
@@ -115,7 +115,7 @@ static void macio_nvram_realizefn(DeviceState *dev, Error **errp)
 
     s->data = g_malloc0(s->size);
 
-    memory_region_init_io(&s->mem, &macio_nvram_ops, s, "macio-nvram",
+    memory_region_init_io(&s->mem, NULL, &macio_nvram_ops, s, "macio-nvram",
                           s->size << s->it_shift);
     sysbus_init_mmio(d, &s->mem);
 }
diff --git a/hw/openrisc/openrisc_sim.c b/hw/openrisc/openrisc_sim.c
index 49bab1f0f0..924438bcc2 100644
--- a/hw/openrisc/openrisc_sim.c
+++ b/hw/openrisc/openrisc_sim.c
@@ -115,7 +115,7 @@ static void openrisc_sim_init(QEMUMachineInitArgs *args)
     }
 
     ram = g_malloc(sizeof(*ram));
-    memory_region_init_ram(ram, "openrisc.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "openrisc.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(get_system_memory(), 0, ram);
 
diff --git a/hw/pci-bridge/dec.c b/hw/pci-bridge/dec.c
index cff458b574..3e8447346a 100644
--- a/hw/pci-bridge/dec.c
+++ b/hw/pci-bridge/dec.c
@@ -98,9 +98,9 @@ static int pci_dec_21154_device_init(SysBusDevice *dev)
 
     phb = PCI_HOST_BRIDGE(dev);
 
-    memory_region_init_io(&phb->conf_mem, &pci_host_conf_le_ops,
+    memory_region_init_io(&phb->conf_mem, NULL, &pci_host_conf_le_ops,
                           dev, "pci-conf-idx", 0x1000);
-    memory_region_init_io(&phb->data_mem, &pci_host_data_le_ops,
+    memory_region_init_io(&phb->data_mem, NULL, &pci_host_data_le_ops,
                           dev, "pci-data-idx", 0x1000);
     sysbus_init_mmio(dev, &phb->conf_mem);
     sysbus_init_mmio(dev, &phb->data_mem);
diff --git a/hw/pci-bridge/pci_bridge_dev.c b/hw/pci-bridge/pci_bridge_dev.c
index 971b432474..c2660f1efc 100644
--- a/hw/pci-bridge/pci_bridge_dev.c
+++ b/hw/pci-bridge/pci_bridge_dev.c
@@ -46,7 +46,7 @@ static int pci_bridge_dev_initfn(PCIDevice *dev)
     if (err) {
         goto bridge_error;
     }
-    memory_region_init(&bridge_dev->bar, "shpc-bar", shpc_bar_size(dev));
+    memory_region_init(&bridge_dev->bar, NULL, "shpc-bar", shpc_bar_size(dev));
     err = shpc_init(dev, &br->sec_bus, &bridge_dev->bar, 0);
     if (err) {
         goto shpc_error;
diff --git a/hw/pci-host/apb.c b/hw/pci-host/apb.c
index e0996556e5..7a8ce25789 100644
--- a/hw/pci-host/apb.c
+++ b/hw/pci-host/apb.c
@@ -447,7 +447,7 @@ PCIBus *pci_apb_init(hwaddr special_base,
     sysbus_mmio_map(s, 2, special_base + 0x2000000ULL);
     d = FROM_SYSBUS(APBState, s);
 
-    memory_region_init(&d->pci_mmio, "pci-mmio", 0x100000000ULL);
+    memory_region_init(&d->pci_mmio, NULL, "pci-mmio", 0x100000000ULL);
     memory_region_add_subregion(get_system_memory(), mem_base, &d->pci_mmio);
 
     d->bus = pci_register_bus(&d->busdev.qdev, "pci",
@@ -525,18 +525,18 @@ static int pci_pbm_init_device(SysBusDevice *dev)
     s->pci_irq_in = 0ULL;
 
     /* apb_config */
-    memory_region_init_io(&s->apb_config, &apb_config_ops, s, "apb-config",
+    memory_region_init_io(&s->apb_config, NULL, &apb_config_ops, s, "apb-config",
                           0x10000);
     /* at region 0 */
     sysbus_init_mmio(dev, &s->apb_config);
 
-    memory_region_init_io(&s->pci_config, &pci_config_ops, s, "apb-pci-config",
+    memory_region_init_io(&s->pci_config, NULL, &pci_config_ops, s, "apb-pci-config",
                           0x1000000);
     /* at region 1 */
     sysbus_init_mmio(dev, &s->pci_config);
 
     /* pci_ioport */
-    memory_region_init_io(&s->pci_ioport, &pci_ioport_ops, s,
+    memory_region_init_io(&s->pci_ioport, NULL, &pci_ioport_ops, s,
                           "apb-pci-ioport", 0x10000);
     /* at region 2 */
     sysbus_init_mmio(dev, &s->pci_ioport);
diff --git a/hw/pci-host/bonito.c b/hw/pci-host/bonito.c
index 974150bfc1..ae007750c0 100644
--- a/hw/pci-host/bonito.c
+++ b/hw/pci-host/bonito.c
@@ -722,29 +722,29 @@ static int bonito_initfn(PCIDevice *dev)
     pci_config_set_prog_interface(dev->config, 0x00);
 
     /* set the north bridge register mapping */
-    memory_region_init_io(&s->iomem, &bonito_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &bonito_ops, s,
                           "north-bridge-register", BONITO_INTERNAL_REG_SIZE);
     sysbus_init_mmio(sysbus, &s->iomem);
     sysbus_mmio_map(sysbus, 0, BONITO_INTERNAL_REG_BASE);
 
     /* set the north bridge pci configure  mapping */
-    memory_region_init_io(&phb->conf_mem, &bonito_pciconf_ops, s,
+    memory_region_init_io(&phb->conf_mem, NULL, &bonito_pciconf_ops, s,
                           "north-bridge-pci-config", BONITO_PCICONFIG_SIZE);
     sysbus_init_mmio(sysbus, &phb->conf_mem);
     sysbus_mmio_map(sysbus, 1, BONITO_PCICONFIG_BASE);
 
     /* set the south bridge pci configure  mapping */
-    memory_region_init_io(&phb->data_mem, &bonito_spciconf_ops, s,
+    memory_region_init_io(&phb->data_mem, NULL, &bonito_spciconf_ops, s,
                           "south-bridge-pci-config", BONITO_SPCICONFIG_SIZE);
     sysbus_init_mmio(sysbus, &phb->data_mem);
     sysbus_mmio_map(sysbus, 2, BONITO_SPCICONFIG_BASE);
 
-    memory_region_init_io(&s->iomem_ldma, &bonito_ldma_ops, s,
+    memory_region_init_io(&s->iomem_ldma, NULL, &bonito_ldma_ops, s,
                           "ldma", 0x100);
     sysbus_init_mmio(sysbus, &s->iomem_ldma);
     sysbus_mmio_map(sysbus, 3, 0xbfe00200);
 
-    memory_region_init_io(&s->iomem_cop, &bonito_cop_ops, s,
+    memory_region_init_io(&s->iomem_cop, NULL, &bonito_cop_ops, s,
                           "cop", 0x100);
     sysbus_init_mmio(sysbus, &s->iomem_cop);
     sysbus_mmio_map(sysbus, 4, 0xbfe00300);
diff --git a/hw/pci-host/grackle.c b/hw/pci-host/grackle.c
index 69344d9f6a..da0fedbbc9 100644
--- a/hw/pci-host/grackle.c
+++ b/hw/pci-host/grackle.c
@@ -76,8 +76,8 @@ PCIBus *pci_grackle_init(uint32_t base, qemu_irq *pic,
     phb = PCI_HOST_BRIDGE(dev);
     d = GRACKLE_PCI_HOST_BRIDGE(dev);
 
-    memory_region_init(&d->pci_mmio, "pci-mmio", 0x100000000ULL);
-    memory_region_init_alias(&d->pci_hole, "pci-hole", &d->pci_mmio,
+    memory_region_init(&d->pci_mmio, NULL, "pci-mmio", 0x100000000ULL);
+    memory_region_init_alias(&d->pci_hole, NULL, "pci-hole", &d->pci_mmio,
                              0x80000000ULL, 0x7e000000ULL);
     memory_region_add_subregion(address_space_mem, 0x80000000ULL,
                                 &d->pci_hole);
@@ -104,9 +104,9 @@ static int pci_grackle_init_device(SysBusDevice *dev)
 
     phb = PCI_HOST_BRIDGE(dev);
 
-    memory_region_init_io(&phb->conf_mem, &pci_host_conf_le_ops,
+    memory_region_init_io(&phb->conf_mem, NULL, &pci_host_conf_le_ops,
                           dev, "pci-conf-idx", 0x1000);
-    memory_region_init_io(&phb->data_mem, &pci_host_data_le_ops,
+    memory_region_init_io(&phb->data_mem, NULL, &pci_host_data_le_ops,
                           dev, "pci-data-idx", 0x1000);
     sysbus_init_mmio(dev, &phb->conf_mem);
     sysbus_init_mmio(dev, &phb->data_mem);
diff --git a/hw/pci-host/pam.c b/hw/pci-host/pam.c
index 7181bd68eb..ec935f440a 100644
--- a/hw/pci-host/pam.c
+++ b/hw/pci-host/pam.c
@@ -56,17 +56,17 @@ void init_pam(MemoryRegion *ram_memory, MemoryRegion *system_memory,
     int i;
 
     /* RAM */
-    memory_region_init_alias(&mem->alias[3], "pam-ram", ram_memory,
+    memory_region_init_alias(&mem->alias[3], NULL, "pam-ram", ram_memory,
                              start, size);
     /* ROM (XXX: not quite correct) */
-    memory_region_init_alias(&mem->alias[1], "pam-rom", ram_memory,
+    memory_region_init_alias(&mem->alias[1], NULL, "pam-rom", ram_memory,
                              start, size);
     memory_region_set_readonly(&mem->alias[1], true);
 
     /* XXX: should distinguish read/write cases */
-    memory_region_init_alias(&mem->alias[0], "pam-pci", pci_address_space,
+    memory_region_init_alias(&mem->alias[0], NULL, "pam-pci", pci_address_space,
                              start, size);
-    memory_region_init_alias(&mem->alias[2], "pam-pci", pci_address_space,
+    memory_region_init_alias(&mem->alias[2], NULL, "pam-pci", pci_address_space,
                              start, size);
 
     for (i = 0; i < 4; ++i) {
diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
index f9e68c3099..4d77b1ee03 100644
--- a/hw/pci-host/piix.c
+++ b/hw/pci-host/piix.c
@@ -201,12 +201,12 @@ static int i440fx_pcihost_initfn(SysBusDevice *dev)
 {
     PCIHostState *s = PCI_HOST_BRIDGE(dev);
 
-    memory_region_init_io(&s->conf_mem, &pci_host_conf_le_ops, s,
+    memory_region_init_io(&s->conf_mem, NULL, &pci_host_conf_le_ops, s,
                           "pci-conf-idx", 4);
     sysbus_add_io(dev, 0xcf8, &s->conf_mem);
     sysbus_init_ioports(&s->busdev, 0xcf8, 4);
 
-    memory_region_init_io(&s->data_mem, &pci_host_data_le_ops, s,
+    memory_region_init_io(&s->data_mem, NULL, &pci_host_data_le_ops, s,
                           "pci-conf-data", 4);
     sysbus_add_io(dev, 0xcfc, &s->data_mem);
     sysbus_init_ioports(&s->busdev, 0xcfc, 4);
@@ -260,17 +260,17 @@ static PCIBus *i440fx_common_init(const char *device_name,
     f->system_memory = address_space_mem;
     f->pci_address_space = pci_address_space;
     f->ram_memory = ram_memory;
-    memory_region_init_alias(&f->pci_hole, "pci-hole", f->pci_address_space,
+    memory_region_init_alias(&f->pci_hole, NULL, "pci-hole", f->pci_address_space,
                              pci_hole_start, pci_hole_size);
     memory_region_add_subregion(f->system_memory, pci_hole_start, &f->pci_hole);
-    memory_region_init_alias(&f->pci_hole_64bit, "pci-hole64",
+    memory_region_init_alias(&f->pci_hole_64bit, NULL, "pci-hole64",
                              f->pci_address_space,
                              pci_hole64_start, pci_hole64_size);
     if (pci_hole64_size) {
         memory_region_add_subregion(f->system_memory, pci_hole64_start,
                                     &f->pci_hole_64bit);
     }
-    memory_region_init_alias(&f->smram_region, "smram-region",
+    memory_region_init_alias(&f->smram_region, NULL, "smram-region",
                              f->pci_address_space, 0xa0000, 0x20000);
     memory_region_add_subregion_overlap(f->system_memory, 0xa0000,
                                         &f->smram_region, 1);
@@ -549,7 +549,7 @@ static int piix3_initfn(PCIDevice *dev)
 
     isa_bus_new(DEVICE(d), pci_address_space_io(dev));
 
-    memory_region_init_io(&d->rcr_mem, &rcr_ops, d, "piix3-reset-control", 1);
+    memory_region_init_io(&d->rcr_mem, NULL, &rcr_ops, d, "piix3-reset-control", 1);
     memory_region_add_subregion_overlap(pci_address_space_io(dev), RCR_IOPORT,
                                         &d->rcr_mem, 1);
 
diff --git a/hw/pci-host/ppce500.c b/hw/pci-host/ppce500.c
index 5e7ad94388..7d8c59b34c 100644
--- a/hw/pci-host/ppce500.c
+++ b/hw/pci-host/ppce500.c
@@ -330,7 +330,7 @@ static int e500_pcihost_bridge_initfn(PCIDevice *d)
         (d->config[PCI_HEADER_TYPE] & PCI_HEADER_TYPE_MULTI_FUNCTION) |
         PCI_HEADER_TYPE_BRIDGE;
 
-    memory_region_init_alias(&b->bar0, "e500-pci-bar0", &ccsr->ccsr_space,
+    memory_region_init_alias(&b->bar0, NULL, "e500-pci-bar0", &ccsr->ccsr_space,
                              0, int128_get64(ccsr->ccsr_space.size));
     pci_register_bar(d, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &b->bar0);
 
@@ -352,7 +352,7 @@ static int e500_pcihost_initfn(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->irq[i]);
     }
 
-    memory_region_init(&s->pio, "pci-pio", PCIE500_PCI_IOLEN);
+    memory_region_init(&s->pio, NULL, "pci-pio", PCIE500_PCI_IOLEN);
 
     b = pci_register_bus(DEVICE(dev), NULL, mpc85xx_pci_set_irq,
                          mpc85xx_pci_map_irq, s->irq, address_space_mem,
@@ -361,12 +361,12 @@ static int e500_pcihost_initfn(SysBusDevice *dev)
 
     pci_create_simple(b, 0, "e500-host-bridge");
 
-    memory_region_init(&s->container, "pci-container", PCIE500_ALL_SIZE);
-    memory_region_init_io(&h->conf_mem, &pci_host_conf_be_ops, h,
+    memory_region_init(&s->container, NULL, "pci-container", PCIE500_ALL_SIZE);
+    memory_region_init_io(&h->conf_mem, NULL, &pci_host_conf_be_ops, h,
                           "pci-conf-idx", 4);
-    memory_region_init_io(&h->data_mem, &pci_host_data_le_ops, h,
+    memory_region_init_io(&h->data_mem, NULL, &pci_host_data_le_ops, h,
                           "pci-conf-data", 4);
-    memory_region_init_io(&s->iomem, &e500_pci_reg_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &e500_pci_reg_ops, s,
                           "pci.reg", PCIE500_REG_SIZE);
     memory_region_add_subregion(&s->container, PCIE500_CFGADDR, &h->conf_mem);
     memory_region_add_subregion(&s->container, PCIE500_CFGDATA, &h->data_mem);
diff --git a/hw/pci-host/prep.c b/hw/pci-host/prep.c
index 61302539ab..024cd51dbc 100644
--- a/hw/pci-host/prep.c
+++ b/hw/pci-host/prep.c
@@ -125,20 +125,20 @@ static void raven_pcihost_realizefn(DeviceState *d, Error **errp)
 
     pci_bus_irqs(&s->pci_bus, prep_set_irq, prep_map_irq, s->irq, 4);
 
-    memory_region_init_io(&h->conf_mem, &pci_host_conf_be_ops, s,
+    memory_region_init_io(&h->conf_mem, NULL, &pci_host_conf_be_ops, s,
                           "pci-conf-idx", 1);
     sysbus_add_io(dev, 0xcf8, &h->conf_mem);
     sysbus_init_ioports(&h->busdev, 0xcf8, 1);
 
-    memory_region_init_io(&h->data_mem, &pci_host_data_be_ops, s,
+    memory_region_init_io(&h->data_mem, NULL, &pci_host_data_be_ops, s,
                           "pci-conf-data", 1);
     sysbus_add_io(dev, 0xcfc, &h->data_mem);
     sysbus_init_ioports(&h->busdev, 0xcfc, 1);
 
-    memory_region_init_io(&h->mmcfg, &PPC_PCIIO_ops, s, "pciio", 0x00400000);
+    memory_region_init_io(&h->mmcfg, NULL, &PPC_PCIIO_ops, s, "pciio", 0x00400000);
     memory_region_add_subregion(address_space_mem, 0x80800000, &h->mmcfg);
 
-    memory_region_init_io(&s->intack, &PPC_intack_ops, s, "pci-intack", 1);
+    memory_region_init_io(&s->intack, NULL, &PPC_intack_ops, s, "pci-intack", 1);
     memory_region_add_subregion(address_space_mem, 0xbffffff0, &s->intack);
 
     /* TODO Remove once realize propagates to child devices. */
diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
index 24df6b55cb..70e7d8b5c8 100644
--- a/hw/pci-host/q35.c
+++ b/hw/pci-host/q35.c
@@ -40,12 +40,12 @@ static int q35_host_init(SysBusDevice *dev)
     PCIHostState *pci = FROM_SYSBUS(PCIHostState, dev);
     Q35PCIHost *s = Q35_HOST_DEVICE(&dev->qdev);
 
-    memory_region_init_io(&pci->conf_mem, &pci_host_conf_le_ops, pci,
+    memory_region_init_io(&pci->conf_mem, NULL, &pci_host_conf_le_ops, pci,
                           "pci-conf-idx", 4);
     sysbus_add_io(dev, MCH_HOST_BRIDGE_CONFIG_ADDR, &pci->conf_mem);
     sysbus_init_ioports(&pci->busdev, MCH_HOST_BRIDGE_CONFIG_ADDR, 4);
 
-    memory_region_init_io(&pci->data_mem, &pci_host_data_le_ops, pci,
+    memory_region_init_io(&pci->data_mem, NULL, &pci_host_data_le_ops, pci,
                           "pci-conf-data", 4);
     sysbus_add_io(dev, MCH_HOST_BRIDGE_CONFIG_DATA, &pci->data_mem);
     sysbus_init_ioports(&pci->busdev, MCH_HOST_BRIDGE_CONFIG_DATA, 4);
@@ -245,7 +245,7 @@ static int mch_init(PCIDevice *d)
     MCHPCIState *mch = MCH_PCI_DEVICE(d);
 
     /* setup pci memory regions */
-    memory_region_init_alias(&mch->pci_hole, "pci-hole",
+    memory_region_init_alias(&mch->pci_hole, NULL, "pci-hole",
                              mch->pci_address_space,
                              mch->below_4g_mem_size,
                              0x100000000ULL - mch->below_4g_mem_size);
@@ -253,7 +253,7 @@ static int mch_init(PCIDevice *d)
                                 &mch->pci_hole);
     pci_hole64_size = (sizeof(hwaddr) == 4 ? 0 :
                        ((uint64_t)1 << 62));
-    memory_region_init_alias(&mch->pci_hole_64bit, "pci-hole64",
+    memory_region_init_alias(&mch->pci_hole_64bit, NULL, "pci-hole64",
                              mch->pci_address_space,
                              0x100000000ULL + mch->above_4g_mem_size,
                              pci_hole64_size);
@@ -264,7 +264,7 @@ static int mch_init(PCIDevice *d)
     }
     /* smram */
     cpu_smm_register(&mch_set_smm, mch);
-    memory_region_init_alias(&mch->smram_region, "smram-region",
+    memory_region_init_alias(&mch->smram_region, NULL, "smram-region",
                              mch->pci_address_space, 0xa0000, 0x20000);
     memory_region_add_subregion_overlap(mch->system_memory, 0xa0000,
                                         &mch->smram_region, 1);
diff --git a/hw/pci-host/uninorth.c b/hw/pci-host/uninorth.c
index fff235d523..b72659d43a 100644
--- a/hw/pci-host/uninorth.c
+++ b/hw/pci-host/uninorth.c
@@ -152,9 +152,9 @@ static int pci_unin_main_init_device(SysBusDevice *dev)
     /* Uninorth main bus */
     h = PCI_HOST_BRIDGE(dev);
 
-    memory_region_init_io(&h->conf_mem, &pci_host_conf_le_ops,
+    memory_region_init_io(&h->conf_mem, NULL, &pci_host_conf_le_ops,
                           dev, "pci-conf-idx", 0x1000);
-    memory_region_init_io(&h->data_mem, &unin_data_ops, dev,
+    memory_region_init_io(&h->data_mem, NULL, &unin_data_ops, dev,
                           "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);
     sysbus_init_mmio(dev, &h->data_mem);
@@ -170,9 +170,9 @@ static int pci_u3_agp_init_device(SysBusDevice *dev)
     /* Uninorth U3 AGP bus */
     h = PCI_HOST_BRIDGE(dev);
 
-    memory_region_init_io(&h->conf_mem, &pci_host_conf_le_ops,
+    memory_region_init_io(&h->conf_mem, NULL, &pci_host_conf_le_ops,
                           dev, "pci-conf-idx", 0x1000);
-    memory_region_init_io(&h->data_mem, &unin_data_ops, dev,
+    memory_region_init_io(&h->data_mem, NULL, &unin_data_ops, dev,
                           "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);
     sysbus_init_mmio(dev, &h->data_mem);
@@ -187,9 +187,9 @@ static int pci_unin_agp_init_device(SysBusDevice *dev)
     /* Uninorth AGP bus */
     h = PCI_HOST_BRIDGE(dev);
 
-    memory_region_init_io(&h->conf_mem, &pci_host_conf_le_ops,
+    memory_region_init_io(&h->conf_mem, NULL, &pci_host_conf_le_ops,
                           dev, "pci-conf-idx", 0x1000);
-    memory_region_init_io(&h->data_mem, &pci_host_data_le_ops,
+    memory_region_init_io(&h->data_mem, NULL, &pci_host_data_le_ops,
                           dev, "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);
     sysbus_init_mmio(dev, &h->data_mem);
@@ -203,9 +203,9 @@ static int pci_unin_internal_init_device(SysBusDevice *dev)
     /* Uninorth internal bus */
     h = PCI_HOST_BRIDGE(dev);
 
-    memory_region_init_io(&h->conf_mem, &pci_host_conf_le_ops,
+    memory_region_init_io(&h->conf_mem, NULL, &pci_host_conf_le_ops,
                           dev, "pci-conf-idx", 0x1000);
-    memory_region_init_io(&h->data_mem, &pci_host_data_le_ops,
+    memory_region_init_io(&h->data_mem, NULL, &pci_host_data_le_ops,
                           dev, "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);
     sysbus_init_mmio(dev, &h->data_mem);
@@ -228,8 +228,8 @@ PCIBus *pci_pmac_init(qemu_irq *pic,
     s = SYS_BUS_DEVICE(dev);
     h = PCI_HOST_BRIDGE(s);
     d = UNI_NORTH_PCI_HOST_BRIDGE(dev);
-    memory_region_init(&d->pci_mmio, "pci-mmio", 0x100000000ULL);
-    memory_region_init_alias(&d->pci_hole, "pci-hole", &d->pci_mmio,
+    memory_region_init(&d->pci_mmio, NULL, "pci-mmio", 0x100000000ULL);
+    memory_region_init_alias(&d->pci_hole, NULL, "pci-hole", &d->pci_mmio,
                              0x80000000ULL, 0x70000000ULL);
     memory_region_add_subregion(address_space_mem, 0x80000000ULL,
                                 &d->pci_hole);
@@ -294,8 +294,8 @@ PCIBus *pci_pmac_u3_init(qemu_irq *pic,
     h = PCI_HOST_BRIDGE(dev);
     d = U3_AGP_HOST_BRIDGE(dev);
 
-    memory_region_init(&d->pci_mmio, "pci-mmio", 0x100000000ULL);
-    memory_region_init_alias(&d->pci_hole, "pci-hole", &d->pci_mmio,
+    memory_region_init(&d->pci_mmio, NULL, "pci-mmio", 0x100000000ULL);
+    memory_region_init_alias(&d->pci_hole, NULL, "pci-hole", &d->pci_mmio,
                              0x80000000ULL, 0x70000000ULL);
     memory_region_add_subregion(address_space_mem, 0x80000000ULL,
                                 &d->pci_hole);
diff --git a/hw/pci-host/versatile.c b/hw/pci-host/versatile.c
index 2f996d9549..f7df27425a 100644
--- a/hw/pci-host/versatile.c
+++ b/hw/pci-host/versatile.c
@@ -381,8 +381,8 @@ static void pci_vpb_init(Object *obj)
     PCIHostState *h = PCI_HOST_BRIDGE(obj);
     PCIVPBState *s = PCI_VPB(obj);
 
-    memory_region_init(&s->pci_io_space, "pci_io", 1ULL << 32);
-    memory_region_init(&s->pci_mem_space, "pci_mem", 1ULL << 32);
+    memory_region_init(&s->pci_io_space, NULL, "pci_io", 1ULL << 32);
+    memory_region_init(&s->pci_mem_space, NULL, "pci_mem", 1ULL << 32);
 
     pci_bus_new_inplace(&s->pci_bus, DEVICE(obj), "pci",
                         &s->pci_mem_space, &s->pci_io_space,
@@ -424,20 +424,20 @@ static void pci_vpb_realize(DeviceState *dev, Error **errp)
      * 3 : PCI IO window
      * 4..6 : PCI memory windows
      */
-    memory_region_init_io(&s->controlregs, &pci_vpb_reg_ops, s, "pci-vpb-regs",
+    memory_region_init_io(&s->controlregs, NULL, &pci_vpb_reg_ops, s, "pci-vpb-regs",
                           0x1000);
     sysbus_init_mmio(sbd, &s->controlregs);
-    memory_region_init_io(&s->mem_config, &pci_vpb_config_ops, s,
+    memory_region_init_io(&s->mem_config, NULL, &pci_vpb_config_ops, s,
                           "pci-vpb-selfconfig", 0x1000000);
     sysbus_init_mmio(sbd, &s->mem_config);
-    memory_region_init_io(&s->mem_config2, &pci_vpb_config_ops, s,
+    memory_region_init_io(&s->mem_config2, NULL, &pci_vpb_config_ops, s,
                           "pci-vpb-config", 0x1000000);
     sysbus_init_mmio(sbd, &s->mem_config2);
 
     /* The window into I/O space is always into a fixed base address;
      * its size is the same for both realview and versatile.
      */
-    memory_region_init_alias(&s->pci_io_window, "pci-vbp-io-window",
+    memory_region_init_alias(&s->pci_io_window, NULL, "pci-vbp-io-window",
                              &s->pci_io_space, 0, 0x100000);
 
     sysbus_init_mmio(sbd, &s->pci_io_space);
@@ -447,7 +447,7 @@ static void pci_vpb_realize(DeviceState *dev, Error **errp)
      * offsets are guest controllable via the IMAP registers.
      */
     for (i = 0; i < 3; i++) {
-        memory_region_init_alias(&s->pci_mem_window[i], "pci-vbp-window",
+        memory_region_init_alias(&s->pci_mem_window[i], NULL, "pci-vbp-window",
                                  &s->pci_mem_space, 0, s->mem_win_size[i]);
         sysbus_init_mmio(sbd, &s->pci_mem_window[i]);
     }
diff --git a/hw/pci/msix.c b/hw/pci/msix.c
index 6da75ec693..83dfc7a717 100644
--- a/hw/pci/msix.c
+++ b/hw/pci/msix.c
@@ -280,10 +280,10 @@ int msix_init(struct PCIDevice *dev, unsigned short nentries,
 
     msix_mask_all(dev, nentries);
 
-    memory_region_init_io(&dev->msix_table_mmio, &msix_table_mmio_ops, dev,
+    memory_region_init_io(&dev->msix_table_mmio, NULL, &msix_table_mmio_ops, dev,
                           "msix-table", table_size);
     memory_region_add_subregion(table_bar, table_offset, &dev->msix_table_mmio);
-    memory_region_init_io(&dev->msix_pba_mmio, &msix_pba_mmio_ops, dev,
+    memory_region_init_io(&dev->msix_pba_mmio, NULL, &msix_pba_mmio_ops, dev,
                           "msix-pba", pba_size);
     memory_region_add_subregion(pba_bar, pba_offset, &dev->msix_pba_mmio);
 
@@ -311,7 +311,7 @@ int msix_init_exclusive_bar(PCIDevice *dev, unsigned short nentries,
     }
 
     name = g_strdup_printf("%s-msix", dev->name);
-    memory_region_init(&dev->msix_exclusive_bar, name, MSIX_EXCLUSIVE_BAR_SIZE);
+    memory_region_init(&dev->msix_exclusive_bar, NULL, name, MSIX_EXCLUSIVE_BAR_SIZE);
     g_free(name);
 
     ret = msix_init(dev, nentries, &dev->msix_exclusive_bar, bar_nr,
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 61b681a91f..a29a385c9e 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -811,7 +811,7 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus,
         dma_as = &address_space_memory;
     }
 
-    memory_region_init_alias(&pci_dev->bus_master_enable_region, "bus master",
+    memory_region_init_alias(&pci_dev->bus_master_enable_region, NULL, "bus master",
                              dma_as->root, 0, memory_region_size(dma_as->root));
     memory_region_set_enabled(&pci_dev->bus_master_enable_region, false);
     address_space_init(&pci_dev->bus_master_as, &pci_dev->bus_master_enable_region,
@@ -1945,7 +1945,7 @@ static int pci_add_option_rom(PCIDevice *pdev, bool is_default_rom)
         snprintf(name, sizeof(name), "%s.rom", object_get_typename(OBJECT(pdev)));
     }
     pdev->has_rom = true;
-    memory_region_init_ram(&pdev->rom, name, size);
+    memory_region_init_ram(&pdev->rom, NULL, name, size);
     vmstate_register_ram(&pdev->rom, &pdev->qdev);
     ptr = memory_region_get_ram_ptr(&pdev->rom);
     load_image(path, ptr);
diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
index 24be6c5067..28ae65e151 100644
--- a/hw/pci/pci_bridge.c
+++ b/hw/pci/pci_bridge.c
@@ -147,7 +147,7 @@ static void pci_bridge_init_alias(PCIBridge *bridge, MemoryRegion *alias,
      * Apparently no way to do this with existing memory APIs. */
     pcibus_t size = enabled && limit >= base ? limit + 1 - base : 0;
 
-    memory_region_init_alias(alias, name, space, base, size);
+    memory_region_init_alias(alias, NULL, name, space, base, size);
     memory_region_add_subregion_overlap(parent_space, base, alias, 1);
 }
 
@@ -156,13 +156,13 @@ static void pci_bridge_init_vga_aliases(PCIBridge *br, PCIBus *parent,
 {
     uint16_t brctl = pci_get_word(br->dev.config + PCI_BRIDGE_CONTROL);
 
-    memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_IO_LO],
+    memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_IO_LO], NULL,
                              "pci_bridge_vga_io_lo", &br->address_space_io,
                              QEMU_PCI_VGA_IO_LO_BASE, QEMU_PCI_VGA_IO_LO_SIZE);
-    memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_IO_HI],
+    memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_IO_HI], NULL,
                              "pci_bridge_vga_io_hi", &br->address_space_io,
                              QEMU_PCI_VGA_IO_HI_BASE, QEMU_PCI_VGA_IO_HI_SIZE);
-    memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_MEM],
+    memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_MEM], NULL,
                              "pci_bridge_vga_mem", &br->address_space_mem,
                              QEMU_PCI_VGA_MEM_BASE, QEMU_PCI_VGA_MEM_SIZE);
 
@@ -367,9 +367,9 @@ int pci_bridge_initfn(PCIDevice *dev, const char *typename)
     sec_bus->parent_dev = dev;
     sec_bus->map_irq = br->map_irq ? br->map_irq : pci_swizzle_map_irq_fn;
     sec_bus->address_space_mem = &br->address_space_mem;
-    memory_region_init(&br->address_space_mem, "pci_bridge_pci", INT64_MAX);
+    memory_region_init(&br->address_space_mem, NULL, "pci_bridge_pci", INT64_MAX);
     sec_bus->address_space_io = &br->address_space_io;
-    memory_region_init(&br->address_space_io, "pci_bridge_io", 65536);
+    memory_region_init(&br->address_space_io, NULL, "pci_bridge_io", 65536);
     br->windows = pci_bridge_region_init(br);
     QLIST_INIT(&sec_bus->child);
     QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling);
diff --git a/hw/pci/pcie_host.c b/hw/pci/pcie_host.c
index b2d942bce1..26f2007fd5 100644
--- a/hw/pci/pcie_host.c
+++ b/hw/pci/pcie_host.c
@@ -130,7 +130,7 @@ void pcie_host_mmcfg_map(PCIExpressHost *e, hwaddr addr,
     assert(size >= PCIE_MMCFG_SIZE_MIN);
     assert(size <= PCIE_MMCFG_SIZE_MAX);
     e->size = size;
-    memory_region_init_io(&e->mmio, &pcie_mmcfg_ops, e, "pcie-mmcfg", e->size);
+    memory_region_init_io(&e->mmio, NULL, &pcie_mmcfg_ops, e, "pcie-mmcfg", e->size);
     e->base_addr = addr;
     memory_region_add_subregion(get_system_memory(), e->base_addr, &e->mmio);
 }
diff --git a/hw/pci/shpc.c b/hw/pci/shpc.c
index d35c2ee965..c4eae07d38 100644
--- a/hw/pci/shpc.c
+++ b/hw/pci/shpc.c
@@ -612,7 +612,7 @@ int shpc_init(PCIDevice *d, PCIBus *sec_bus, MemoryRegion *bar, unsigned offset)
     }
 
     /* TODO: init cmask */
-    memory_region_init_io(&shpc->mmio, &shpc_mmio_ops, d, "shpc-mmio",
+    memory_region_init_io(&shpc->mmio, NULL, &shpc_mmio_ops, d, "shpc-mmio",
                           SHPC_SIZEOF(d));
     shpc_cap_update_dword(d);
     memory_region_add_subregion(bar, offset, &shpc->mmio);
diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
index 38f799031a..b45fe91b82 100644
--- a/hw/ppc/e500.c
+++ b/hw/ppc/e500.c
@@ -651,7 +651,7 @@ void ppce500_init(PPCE500Params *params)
     params->ram_size = ram_size;
 
     /* Register Memory */
-    memory_region_init_ram(ram, "mpc8544ds.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "mpc8544ds.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, 0, ram);
 
@@ -783,7 +783,7 @@ static int e500_ccsr_initfn(SysBusDevice *dev)
     PPCE500CCSRState *ccsr;
 
     ccsr = CCSR(dev);
-    memory_region_init(&ccsr->ccsr_space, "e500-ccsr",
+    memory_region_init(&ccsr->ccsr_space, NULL, "e500-ccsr",
                        MPC8544_CCSRBAR_SIZE);
     return 0;
 }
diff --git a/hw/ppc/mac_newworld.c b/hw/ppc/mac_newworld.c
index 3badfa3adb..2133e2dc9e 100644
--- a/hw/ppc/mac_newworld.c
+++ b/hw/ppc/mac_newworld.c
@@ -196,12 +196,12 @@ static void ppc_core99_init(QEMUMachineInitArgs *args)
     }
 
     /* allocate RAM */
-    memory_region_init_ram(ram, "ppc_core99.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "ppc_core99.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(get_system_memory(), 0, ram);
 
     /* allocate and load BIOS */
-    memory_region_init_ram(bios, "ppc_core99.bios", BIOS_SIZE);
+    memory_region_init_ram(bios, NULL, "ppc_core99.bios", BIOS_SIZE);
     vmstate_register_ram_global(bios);
     if (bios_name == NULL)
         bios_name = PROM_FILENAME;
@@ -290,10 +290,10 @@ static void ppc_core99_init(QEMUMachineInitArgs *args)
     isa_mmio_init(0xf2000000, 0x00800000);
 
     /* UniN init: XXX should be a real device */
-    memory_region_init_io(unin_memory, &unin_ops, token, "unin", 0x1000);
+    memory_region_init_io(unin_memory, NULL, &unin_ops, token, "unin", 0x1000);
     memory_region_add_subregion(get_system_memory(), 0xf8000000, unin_memory);
 
-    memory_region_init_io(unin2_memory, &unin_ops, token, "unin", 0x1000);
+    memory_region_init_io(unin2_memory, NULL, &unin_ops, token, "unin", 0x1000);
     memory_region_add_subregion(get_system_memory(), 0xf3000000, unin2_memory);
 
     openpic_irqs = g_malloc0(smp_cpus * sizeof(qemu_irq *));
@@ -371,7 +371,7 @@ static void ppc_core99_init(QEMUMachineInitArgs *args)
 
     escc_mem = escc_init(0, pic[0x25], pic[0x24],
                          serial_hds[0], serial_hds[1], ESCC_CLOCK, 4);
-    memory_region_init_alias(escc_bar, "escc-bar",
+    memory_region_init_alias(escc_bar, NULL, "escc-bar",
                              escc_mem, 0, memory_region_size(escc_mem));
 
     for(i = 0; i < nb_nics; i++)
diff --git a/hw/ppc/mac_oldworld.c b/hw/ppc/mac_oldworld.c
index 8faff300ff..d5e8178526 100644
--- a/hw/ppc/mac_oldworld.c
+++ b/hw/ppc/mac_oldworld.c
@@ -126,12 +126,12 @@ static void ppc_heathrow_init(QEMUMachineInitArgs *args)
         exit(1);
     }
 
-    memory_region_init_ram(ram, "ppc_heathrow.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "ppc_heathrow.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(sysmem, 0, ram);
 
     /* allocate and load BIOS */
-    memory_region_init_ram(bios, "ppc_heathrow.bios", BIOS_SIZE);
+    memory_region_init_ram(bios, NULL, "ppc_heathrow.bios", BIOS_SIZE);
     vmstate_register_ram_global(bios);
     if (bios_name == NULL)
         bios_name = PROM_FILENAME;
@@ -255,7 +255,7 @@ static void ppc_heathrow_init(QEMUMachineInitArgs *args)
 
     escc_mem = escc_init(0, pic[0x0f], pic[0x10], serial_hds[0],
                                serial_hds[1], ESCC_CLOCK, 4);
-    memory_region_init_alias(escc_bar, "escc-bar",
+    memory_region_init_alias(escc_bar, NULL, "escc-bar",
                              escc_mem, 0, memory_region_size(escc_mem));
 
     for(i = 0; i < nb_nics; i++)
diff --git a/hw/ppc/mpc8544_guts.c b/hw/ppc/mpc8544_guts.c
index d41f615522..56249b4b6a 100644
--- a/hw/ppc/mpc8544_guts.c
+++ b/hw/ppc/mpc8544_guts.c
@@ -119,7 +119,7 @@ static void mpc8544_guts_initfn(Object *obj)
     SysBusDevice *d = SYS_BUS_DEVICE(obj);
     GutsState *s = MPC8544_GUTS(obj);
 
-    memory_region_init_io(&s->iomem, &mpc8544_guts_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &mpc8544_guts_ops, s,
                           "mpc8544.guts", MPC8544_GUTS_MMIO_SIZE);
     sysbus_init_mmio(d, &s->iomem);
 }
diff --git a/hw/ppc/ppc405_boards.c b/hw/ppc/ppc405_boards.c
index f0c7ee9abd..f74e5e52c2 100644
--- a/hw/ppc/ppc405_boards.c
+++ b/hw/ppc/ppc405_boards.c
@@ -164,7 +164,7 @@ static void ref405ep_fpga_init(MemoryRegion *sysmem, uint32_t base)
     MemoryRegion *fpga_memory = g_new(MemoryRegion, 1);
 
     fpga = g_malloc0(sizeof(ref405ep_fpga_t));
-    memory_region_init_io(fpga_memory, &ref405ep_fpga_ops, fpga,
+    memory_region_init_io(fpga_memory, NULL, &ref405ep_fpga_ops, fpga,
                           "fpga", 0x00000100);
     memory_region_add_subregion(sysmem, base, fpga_memory);
     qemu_register_reset(&ref405ep_fpga_reset, fpga);
@@ -197,11 +197,11 @@ static void ref405ep_init(QEMUMachineInitArgs *args)
     MemoryRegion *sysmem = get_system_memory();
 
     /* XXX: fix this */
-    memory_region_init_ram(&ram_memories[0], "ef405ep.ram", 0x08000000);
+    memory_region_init_ram(&ram_memories[0], NULL, "ef405ep.ram", 0x08000000);
     vmstate_register_ram_global(&ram_memories[0]);
     ram_bases[0] = 0;
     ram_sizes[0] = 0x08000000;
-    memory_region_init(&ram_memories[1], "ef405ep.ram1", 0);
+    memory_region_init(&ram_memories[1], NULL, "ef405ep.ram1", 0);
     ram_bases[1] = 0x00000000;
     ram_sizes[1] = 0x00000000;
     ram_size = 128 * 1024 * 1024;
@@ -212,7 +212,7 @@ static void ref405ep_init(QEMUMachineInitArgs *args)
                         33333333, &pic, kernel_filename == NULL ? 0 : 1);
     /* allocate SRAM */
     sram_size = 512 * 1024;
-    memory_region_init_ram(sram, "ef405ep.sram", sram_size);
+    memory_region_init_ram(sram, NULL, "ef405ep.sram", sram_size);
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(sysmem, 0xFFF00000, sram);
     /* allocate and load BIOS */
@@ -244,7 +244,7 @@ static void ref405ep_init(QEMUMachineInitArgs *args)
         printf("Load BIOS from file\n");
 #endif
         bios = g_new(MemoryRegion, 1);
-        memory_region_init_ram(bios, "ef405ep.bios", BIOS_SIZE);
+        memory_region_init_ram(bios, NULL, "ef405ep.bios", BIOS_SIZE);
         vmstate_register_ram_global(bios);
         if (bios_name == NULL)
             bios_name = BIOS_FILENAME;
@@ -490,7 +490,7 @@ static void taihu_cpld_init(MemoryRegion *sysmem, uint32_t base)
     MemoryRegion *cpld_memory = g_new(MemoryRegion, 1);
 
     cpld = g_malloc0(sizeof(taihu_cpld_t));
-    memory_region_init_io(cpld_memory, &taihu_cpld_ops, cpld, "cpld", 0x100);
+    memory_region_init_io(cpld_memory, NULL, &taihu_cpld_ops, cpld, "cpld", 0x100);
     memory_region_add_subregion(sysmem, base, cpld_memory);
     qemu_register_reset(&taihu_cpld_reset, cpld);
 }
@@ -514,12 +514,12 @@ static void taihu_405ep_init(QEMUMachineInitArgs *args)
     DriveInfo *dinfo;
 
     /* RAM is soldered to the board so the size cannot be changed */
-    memory_region_init_ram(&ram_memories[0],
+    memory_region_init_ram(&ram_memories[0], NULL,
                            "taihu_405ep.ram-0", 0x04000000);
     vmstate_register_ram_global(&ram_memories[0]);
     ram_bases[0] = 0;
     ram_sizes[0] = 0x04000000;
-    memory_region_init_ram(&ram_memories[1],
+    memory_region_init_ram(&ram_memories[1], NULL,
                            "taihu_405ep.ram-1", 0x04000000);
     vmstate_register_ram_global(&ram_memories[1]);
     ram_bases[1] = 0x04000000;
@@ -563,7 +563,7 @@ static void taihu_405ep_init(QEMUMachineInitArgs *args)
         if (bios_name == NULL)
             bios_name = BIOS_FILENAME;
         bios = g_new(MemoryRegion, 1);
-        memory_region_init_ram(bios, "taihu_405ep.bios", BIOS_SIZE);
+        memory_region_init_ram(bios, NULL, "taihu_405ep.bios", BIOS_SIZE);
         vmstate_register_ram_global(bios);
         filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
         if (filename) {
diff --git a/hw/ppc/ppc405_uc.c b/hw/ppc/ppc405_uc.c
index c6c909e05e..290f71ab69 100644
--- a/hw/ppc/ppc405_uc.c
+++ b/hw/ppc/ppc405_uc.c
@@ -390,7 +390,7 @@ static void ppc4xx_opba_init(hwaddr base)
 #ifdef DEBUG_OPBA
     printf("%s: offset " TARGET_FMT_plx "\n", __func__, base);
 #endif
-    memory_region_init_io(&opba->io, &opba_ops, opba, "opba", 0x002);
+    memory_region_init_io(&opba->io, NULL, &opba_ops, opba, "opba", 0x002);
     memory_region_add_subregion(get_system_memory(), base, &opba->io);
     qemu_register_reset(ppc4xx_opba_reset, opba);
 }
@@ -812,7 +812,7 @@ static void ppc405_gpio_init(hwaddr base)
 #ifdef DEBUG_GPIO
     printf("%s: offset " TARGET_FMT_plx "\n", __func__, base);
 #endif
-    memory_region_init_io(&gpio->io, &ppc405_gpio_ops, gpio, "pgio", 0x038);
+    memory_region_init_io(&gpio->io, NULL, &ppc405_gpio_ops, gpio, "pgio", 0x038);
     memory_region_add_subregion(get_system_memory(), base, &gpio->io);
     qemu_register_reset(&ppc405_gpio_reset, gpio);
 }
@@ -972,9 +972,9 @@ static void ppc405_ocm_init(CPUPPCState *env)
 
     ocm = g_malloc0(sizeof(ppc405_ocm_t));
     /* XXX: Size is 4096 or 0x04000000 */
-    memory_region_init_ram(&ocm->isarc_ram, "ppc405.ocm", 4096);
+    memory_region_init_ram(&ocm->isarc_ram, NULL, "ppc405.ocm", 4096);
     vmstate_register_ram_global(&ocm->isarc_ram);
-    memory_region_init_alias(&ocm->dsarc_ram, "ppc405.dsarc", &ocm->isarc_ram,
+    memory_region_init_alias(&ocm->dsarc_ram, NULL, "ppc405.dsarc", &ocm->isarc_ram,
                              0, 4096);
     qemu_register_reset(&ocm_reset, ocm);
     ppc_dcr_register(env, OCM0_ISARC,
@@ -1222,7 +1222,7 @@ static void ppc405_i2c_init(hwaddr base, qemu_irq irq)
 #ifdef DEBUG_I2C
     printf("%s: offset " TARGET_FMT_plx "\n", __func__, base);
 #endif
-    memory_region_init_io(&i2c->iomem, &i2c_ops, i2c, "i2c", 0x011);
+    memory_region_init_io(&i2c->iomem, NULL, &i2c_ops, i2c, "i2c", 0x011);
     memory_region_add_subregion(get_system_memory(), base, &i2c->iomem);
     qemu_register_reset(ppc4xx_i2c_reset, i2c);
 }
@@ -1501,7 +1501,7 @@ static void ppc4xx_gpt_init(hwaddr base, qemu_irq irqs[5])
 #ifdef DEBUG_GPT
     printf("%s: offset " TARGET_FMT_plx "\n", __func__, base);
 #endif
-    memory_region_init_io(&gpt->iomem, &gpt_ops, gpt, "gpt", 0x0d4);
+    memory_region_init_io(&gpt->iomem, NULL, &gpt_ops, gpt, "gpt", 0x0d4);
     memory_region_add_subregion(get_system_memory(), base, &gpt->iomem);
     qemu_register_reset(ppc4xx_gpt_reset, gpt);
 }
diff --git a/hw/ppc/ppc4xx_devs.c b/hw/ppc/ppc4xx_devs.c
index d8e3dae25c..239aada193 100644
--- a/hw/ppc/ppc4xx_devs.c
+++ b/hw/ppc/ppc4xx_devs.c
@@ -431,7 +431,7 @@ static void sdram_set_bcr(ppc4xx_sdram_t *sdram,
         printf("%s: Map RAM area " TARGET_FMT_plx " " TARGET_FMT_lx "\n",
                __func__, sdram_base(bcr), sdram_size(bcr));
 #endif
-        memory_region_init(&sdram->containers[n], "sdram-containers",
+        memory_region_init(&sdram->containers[n], NULL, "sdram-containers",
                            sdram_size(bcr));
         memory_region_add_subregion(&sdram->containers[n], 0,
                                     &sdram->ram_memories[n]);
@@ -696,7 +696,7 @@ ram_addr_t ppc4xx_sdram_adjust(ram_addr_t ram_size, int nr_banks,
             if (bank_size <= size_left) {
                 char name[32];
                 snprintf(name, sizeof(name), "ppc4xx.sdram%d", i);
-                memory_region_init_ram(&ram_memories[i], name, bank_size);
+                memory_region_init_ram(&ram_memories[i], NULL, name, bank_size);
                 vmstate_register_ram_global(&ram_memories[i]);
                 ram_bases[i] = base;
                 ram_sizes[i] = bank_size;
diff --git a/hw/ppc/ppc4xx_pci.c b/hw/ppc/ppc4xx_pci.c
index 599539bc1d..f227043469 100644
--- a/hw/ppc/ppc4xx_pci.c
+++ b/hw/ppc/ppc4xx_pci.c
@@ -355,12 +355,12 @@ static int ppc4xx_pcihost_initfn(SysBusDevice *dev)
     pci_create_simple(b, 0, "ppc4xx-host-bridge");
 
     /* XXX split into 2 memory regions, one for config space, one for regs */
-    memory_region_init(&s->container, "pci-container", PCI_ALL_SIZE);
-    memory_region_init_io(&h->conf_mem, &pci_host_conf_le_ops, h,
+    memory_region_init(&s->container, NULL, "pci-container", PCI_ALL_SIZE);
+    memory_region_init_io(&h->conf_mem, NULL, &pci_host_conf_le_ops, h,
                           "pci-conf-idx", 4);
-    memory_region_init_io(&h->data_mem, &pci_host_data_le_ops, h,
+    memory_region_init_io(&h->data_mem, NULL, &pci_host_data_le_ops, h,
                           "pci-conf-data", 4);
-    memory_region_init_io(&s->iomem, &pci_reg_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pci_reg_ops, s,
                           "pci.reg", PCI_REG_SIZE);
     memory_region_add_subregion(&s->container, PCIC0_CFGADDR, &h->conf_mem);
     memory_region_add_subregion(&s->container, PCIC0_CFGDATA, &h->data_mem);
diff --git a/hw/ppc/ppce500_spin.c b/hw/ppc/ppce500_spin.c
index ea6541413f..0817f14830 100644
--- a/hw/ppc/ppce500_spin.c
+++ b/hw/ppc/ppce500_spin.c
@@ -191,7 +191,7 @@ static int ppce500_spin_initfn(SysBusDevice *dev)
 
     s = FROM_SYSBUS(SpinState, SYS_BUS_DEVICE(dev));
 
-    memory_region_init_io(&s->iomem, &spin_rw_ops, s, "e500 spin pv device",
+    memory_region_init_io(&s->iomem, NULL, &spin_rw_ops, s, "e500 spin pv device",
                           sizeof(SpinInfo) * MAX_CPUS);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/ppc/prep.c b/hw/ppc/prep.c
index 560a59aa71..899aa301ae 100644
--- a/hw/ppc/prep.c
+++ b/hw/ppc/prep.c
@@ -505,12 +505,12 @@ static void ppc_prep_init(QEMUMachineInitArgs *args)
     }
 
     /* allocate RAM */
-    memory_region_init_ram(ram, "ppc_prep.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "ppc_prep.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(sysmem, 0, ram);
 
     /* allocate and load BIOS */
-    memory_region_init_ram(bios, "ppc_prep.bios", BIOS_SIZE);
+    memory_region_init_ram(bios, NULL, "ppc_prep.bios", BIOS_SIZE);
     memory_region_set_readonly(bios, true);
     memory_region_add_subregion(sysmem, (uint32_t)(-BIOS_SIZE), bios);
     vmstate_register_ram_global(bios);
@@ -621,7 +621,7 @@ static void ppc_prep_init(QEMUMachineInitArgs *args)
     qdev_init_nofail(dev);
 
     /* Register 8 MB of ISA IO space (needed for non-contiguous map) */
-    memory_region_init_io(PPC_io_memory, &PPC_prep_io_ops, sysctrl,
+    memory_region_init_io(PPC_io_memory, NULL, &PPC_prep_io_ops, sysctrl,
                           "ppc-io", 0x00800000);
     memory_region_add_subregion(sysmem, 0x80000000, PPC_io_memory);
 
@@ -658,7 +658,7 @@ static void ppc_prep_init(QEMUMachineInitArgs *args)
 
     /* PowerPC control and status register group */
 #if 0
-    memory_region_init_io(xcsr, &PPC_XCSR_ops, NULL, "ppc-xcsr", 0x1000);
+    memory_region_init_io(xcsr, NULL, &PPC_XCSR_ops, NULL, "ppc-xcsr", 0x1000);
     memory_region_add_subregion(sysmem, 0xFEFF0000, xcsr);
 #endif
 
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index fe34291ffd..c11427648a 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -835,7 +835,7 @@ static void ppc_spapr_init(QEMUMachineInitArgs *args)
         ram_addr_t nonrma_base = rma_alloc_size;
         ram_addr_t nonrma_size = spapr->ram_limit - rma_alloc_size;
 
-        memory_region_init_ram(ram, "ppc_spapr.ram", nonrma_size);
+        memory_region_init_ram(ram, NULL, "ppc_spapr.ram", nonrma_size);
         vmstate_register_ram_global(ram);
         memory_region_add_subregion(sysmem, nonrma_base, ram);
     }
diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index 91bc8e488e..3976af62df 100644
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -151,7 +151,7 @@ sPAPRTCETable *spapr_tce_new_table(uint32_t liobn, size_t window_size)
             "table @ %p, fd=%d\n", tcet, liobn, tcet->table, tcet->fd);
 #endif
 
-    memory_region_init_iommu(&tcet->iommu, &spapr_iommu_ops,
+    memory_region_init_iommu(&tcet->iommu, NULL, &spapr_iommu_ops,
                              "iommu-spapr", UINT64_MAX);
 
     QLIST_INSERT_HEAD(&spapr_tce_tables, tcet, list);
diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index c8c12c8241..65e05d5741 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -581,10 +581,10 @@ static int spapr_phb_init(SysBusDevice *s)
 
     /* Initialize memory regions */
     sprintf(namebuf, "%s.mmio", sphb->dtbusname);
-    memory_region_init(&sphb->memspace, namebuf, INT64_MAX);
+    memory_region_init(&sphb->memspace, NULL, namebuf, INT64_MAX);
 
     sprintf(namebuf, "%s.mmio-alias", sphb->dtbusname);
-    memory_region_init_alias(&sphb->memwindow, namebuf, &sphb->memspace,
+    memory_region_init_alias(&sphb->memwindow, NULL, namebuf, &sphb->memspace,
                              SPAPR_PCI_MEM_WIN_BUS_OFFSET, sphb->mem_win_size);
     memory_region_add_subregion(get_system_memory(), sphb->mem_win_addr,
                                 &sphb->memwindow);
@@ -598,12 +598,12 @@ static int spapr_phb_init(SysBusDevice *s)
      * system_io works around the problem until all the users of
      * old_portion are updated */
     sprintf(namebuf, "%s.io", sphb->dtbusname);
-    memory_region_init(&sphb->iospace, namebuf, SPAPR_PCI_IO_WIN_SIZE);
+    memory_region_init(&sphb->iospace, NULL, namebuf, SPAPR_PCI_IO_WIN_SIZE);
     /* FIXME: fix to support multiple PHBs */
     memory_region_add_subregion(get_system_io(), 0, &sphb->iospace);
 
     sprintf(namebuf, "%s.io-alias", sphb->dtbusname);
-    memory_region_init_io(&sphb->iowindow, &spapr_io_ops, sphb,
+    memory_region_init_io(&sphb->iowindow, NULL, &spapr_io_ops, sphb,
                           namebuf, SPAPR_PCI_IO_WIN_SIZE);
     memory_region_add_subregion(get_system_memory(), sphb->io_win_addr,
                                 &sphb->iowindow);
@@ -613,7 +613,7 @@ static int spapr_phb_init(SysBusDevice *s)
      * from msi_notify()/msix_notify() */
     if (msi_supported) {
         sprintf(namebuf, "%s.msi", sphb->dtbusname);
-        memory_region_init_io(&sphb->msiwindow, &spapr_msi_ops, sphb,
+        memory_region_init_io(&sphb->msiwindow, NULL, &spapr_msi_ops, sphb,
                               namebuf, SPAPR_MSIX_MAX_DEVS * 0x10000);
         memory_region_add_subregion(get_system_memory(), sphb->msi_win_addr,
                                     &sphb->msiwindow);
diff --git a/hw/ppc/virtex_ml507.c b/hw/ppc/virtex_ml507.c
index 709a707243..08e77fbef5 100644
--- a/hw/ppc/virtex_ml507.c
+++ b/hw/ppc/virtex_ml507.c
@@ -190,7 +190,7 @@ static void virtex_init(QEMUMachineInitArgs *args)
     env = &cpu->env;
     qemu_register_reset(main_cpu_reset, cpu);
 
-    memory_region_init_ram(phys_ram, "ram", ram_size);
+    memory_region_init_ram(phys_ram, NULL, "ram", ram_size);
     vmstate_register_ram_global(phys_ram);
     memory_region_add_subregion(address_space_mem, ram_base, phys_ram);
 
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index eb774d90e0..aebbbf1755 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -89,7 +89,7 @@ static void ccw_init(QEMUMachineInitArgs *args)
     virtio_ccw_register_hcalls();
 
     /* allocate RAM */
-    memory_region_init_ram(ram, "s390.ram", my_ram_size);
+    memory_region_init_ram(ram, NULL, "s390.ram", my_ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(sysmem, 0, ram);
 
diff --git a/hw/s390x/s390-virtio.c b/hw/s390x/s390-virtio.c
index 30d1118cdc..edbde00d4d 100644
--- a/hw/s390x/s390-virtio.c
+++ b/hw/s390x/s390-virtio.c
@@ -256,7 +256,7 @@ static void s390_init(QEMUMachineInitArgs *args)
     s390_virtio_register_hcalls();
 
     /* allocate RAM */
-    memory_region_init_ram(ram, "s390.ram", my_ram_size);
+    memory_region_init_ram(ram, NULL, "s390.ram", my_ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(sysmem, 0, ram);
 
diff --git a/hw/scsi/esp-pci.c b/hw/scsi/esp-pci.c
index 029789ae39..384224f3e1 100644
--- a/hw/scsi/esp-pci.c
+++ b/hw/scsi/esp-pci.c
@@ -349,7 +349,7 @@ static int esp_pci_scsi_init(PCIDevice *dev)
     s->dma_memory_write = esp_pci_dma_memory_write;
     s->dma_opaque = pci;
     s->chip_id = TCHI_AM53C974;
-    memory_region_init_io(&pci->io, &esp_pci_io_ops, pci, "esp-io", 0x80);
+    memory_region_init_io(&pci->io, NULL, &esp_pci_io_ops, pci, "esp-io", 0x80);
 
     pci_register_bar(&pci->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &pci->io);
     s->irq = pci->dev.irq[0];
diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
index 0c81a50398..5da5d7a021 100644
--- a/hw/scsi/esp.c
+++ b/hw/scsi/esp.c
@@ -675,7 +675,7 @@ static int sysbus_esp_init(SysBusDevice *dev)
     assert(sysbus->it_shift != -1);
 
     s->chip_id = TCHI_FAS100A;
-    memory_region_init_io(&sysbus->iomem, &sysbus_esp_mem_ops, sysbus,
+    memory_region_init_io(&sysbus->iomem, NULL, &sysbus_esp_mem_ops, sysbus,
                           "esp", ESP_REGS << sysbus->it_shift);
     sysbus_init_mmio(dev, &sysbus->iomem);
 
diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
index 22b8e98697..b31f0b7983 100644
--- a/hw/scsi/lsi53c895a.c
+++ b/hw/scsi/lsi53c895a.c
@@ -2090,9 +2090,9 @@ static int lsi_scsi_init(PCIDevice *dev)
     /* Interrupt pin A */
     pci_conf[PCI_INTERRUPT_PIN] = 0x01;
 
-    memory_region_init_io(&s->mmio_io, &lsi_mmio_ops, s, "lsi-mmio", 0x400);
-    memory_region_init_io(&s->ram_io, &lsi_ram_ops, s, "lsi-ram", 0x2000);
-    memory_region_init_io(&s->io_io, &lsi_io_ops, s, "lsi-io", 256);
+    memory_region_init_io(&s->mmio_io, NULL, &lsi_mmio_ops, s, "lsi-mmio", 0x400);
+    memory_region_init_io(&s->ram_io, NULL, &lsi_ram_ops, s, "lsi-ram", 0x2000);
+    memory_region_init_io(&s->io_io, NULL, &lsi_io_ops, s, "lsi-io", 256);
 
     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->io_io);
     pci_register_bar(&s->dev, 1, 0, &s->mmio_io);
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c
index 65ccb09ba1..ba74f0b33c 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -2098,11 +2098,11 @@ static int megasas_scsi_init(PCIDevice *dev)
     /* Interrupt pin 1 */
     pci_conf[PCI_INTERRUPT_PIN] = 0x01;
 
-    memory_region_init_io(&s->mmio_io, &megasas_mmio_ops, s,
+    memory_region_init_io(&s->mmio_io, NULL, &megasas_mmio_ops, s,
                           "megasas-mmio", 0x4000);
-    memory_region_init_io(&s->port_io, &megasas_port_ops, s,
+    memory_region_init_io(&s->port_io, NULL, &megasas_port_ops, s,
                           "megasas-io", 256);
-    memory_region_init_io(&s->queue_io, &megasas_queue_ops, s,
+    memory_region_init_io(&s->queue_io, NULL, &megasas_queue_ops, s,
                           "megasas-queue", 0x40000);
 
 #ifdef USE_MSIX
diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c
index 7cf4044591..b7a1275e86 100644
--- a/hw/scsi/vmw_pvscsi.c
+++ b/hw/scsi/vmw_pvscsi.c
@@ -1075,7 +1075,7 @@ pvscsi_init(PCIDevice *pci_dev)
     /* Interrupt pin A */
     pci_config_set_interrupt_pin(pci_dev->config, 1);
 
-    memory_region_init_io(&s->io_space, &pvscsi_ops, s,
+    memory_region_init_io(&s->io_space, NULL, &pvscsi_ops, s,
                           "pvscsi-io", PVSCSI_MEM_SPACE_SIZE);
     pci_register_bar(pci_dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->io_space);
 
diff --git a/hw/sd/milkymist-memcard.c b/hw/sd/milkymist-memcard.c
index 61a8aadddd..6de050f6b2 100644
--- a/hw/sd/milkymist-memcard.c
+++ b/hw/sd/milkymist-memcard.c
@@ -253,7 +253,7 @@ static int milkymist_memcard_init(SysBusDevice *dev)
     s->card = sd_init(dinfo ? dinfo->bdrv : NULL, false);
     s->enabled = dinfo ? bdrv_is_inserted(dinfo->bdrv) : 0;
 
-    memory_region_init_io(&s->regs_region, &memcard_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &memcard_mmio_ops, s,
             "milkymist-memcard", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/sd/omap_mmc.c b/hw/sd/omap_mmc.c
index ba9f4b3098..bf5d1fbf6d 100644
--- a/hw/sd/omap_mmc.c
+++ b/hw/sd/omap_mmc.c
@@ -588,7 +588,7 @@ struct omap_mmc_s *omap_mmc_init(hwaddr base,
 
     omap_mmc_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_mmc_ops, s, "omap.mmc", 0x800);
+    memory_region_init_io(&s->iomem, NULL, &omap_mmc_ops, s, "omap.mmc", 0x800);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     /* Instantiate the storage */
@@ -612,7 +612,7 @@ struct omap_mmc_s *omap2_mmc_init(struct omap_target_agent_s *ta,
 
     omap_mmc_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_mmc_ops, s, "omap.mmc",
+    memory_region_init_io(&s->iomem, NULL, &omap_mmc_ops, s, "omap.mmc",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &s->iomem);
 
diff --git a/hw/sd/pl181.c b/hw/sd/pl181.c
index e08fd04e7e..15f7890484 100644
--- a/hw/sd/pl181.c
+++ b/hw/sd/pl181.c
@@ -479,7 +479,7 @@ static int pl181_init(SysBusDevice *dev)
     pl181_state *s = FROM_SYSBUS(pl181_state, dev);
     DriveInfo *dinfo;
 
-    memory_region_init_io(&s->iomem, &pl181_ops, s, "pl181", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl181_ops, s, "pl181", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq[0]);
     sysbus_init_irq(dev, &s->irq[1]);
diff --git a/hw/sd/pxa2xx_mmci.c b/hw/sd/pxa2xx_mmci.c
index 0574d6b26d..90c955fe62 100644
--- a/hw/sd/pxa2xx_mmci.c
+++ b/hw/sd/pxa2xx_mmci.c
@@ -533,7 +533,7 @@ PXA2xxMMCIState *pxa2xx_mmci_init(MemoryRegion *sysmem,
     s->rx_dma = rx_dma;
     s->tx_dma = tx_dma;
 
-    memory_region_init_io(&s->iomem, &pxa2xx_mmci_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_mmci_ops, s,
                           "pxa2xx-mmci", 0x00100000);
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index b9dd4bebc1..ac219c0700 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -1245,7 +1245,7 @@ static void sdhci_realize(DeviceState *dev, Error ** errp)
     s->buf_maxsz = sdhci_get_fifolen(s);
     s->fifo_buffer = g_malloc0(s->buf_maxsz);
     sysbus_init_irq(sbd, &s->irq);
-    memory_region_init_io(&s->iomem, &sdhci_mmio_ops, s, "sdhci",
+    memory_region_init_io(&s->iomem, NULL, &sdhci_mmio_ops, s, "sdhci",
             SDHC_REGISTERS_MAP_SIZE);
     sysbus_init_mmio(sbd, &s->iomem);
 }
diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 3e4818e170..e7794166cf 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -186,7 +186,7 @@ static qemu_irq *r2d_fpga_init(MemoryRegion *sysmem,
 
     s->irl = irl;
 
-    memory_region_init_io(&s->iomem, &r2d_fpga_ops, s, "r2d-fpga", 0x40);
+    memory_region_init_io(&s->iomem, NULL, &r2d_fpga_ops, s, "r2d-fpga", 0x40);
     memory_region_add_subregion(sysmem, base, &s->iomem);
     return qemu_allocate_irqs(r2d_fpga_irq_set, s, NR_IRQS);
 }
@@ -254,7 +254,7 @@ static void r2d_init(QEMUMachineInitArgs *args)
     qemu_register_reset(main_cpu_reset, reset_info);
 
     /* Allocate memory space */
-    memory_region_init_ram(sdram, "r2d.sdram", SDRAM_SIZE);
+    memory_region_init_ram(sdram, NULL, "r2d.sdram", SDRAM_SIZE);
     vmstate_register_ram_global(sdram);
     memory_region_add_subregion(address_space_mem, SDRAM_BASE, sdram);
     /* Register peripherals */
diff --git a/hw/sh4/sh7750.c b/hw/sh4/sh7750.c
index 03e8bd1776..1439ba44e5 100644
--- a/hw/sh4/sh7750.c
+++ b/hw/sh4/sh7750.c
@@ -730,34 +730,34 @@ SH7750State *sh7750_init(SuperHCPU *cpu, MemoryRegion *sysmem)
     s = g_malloc0(sizeof(SH7750State));
     s->cpu = cpu;
     s->periph_freq = 60000000;	/* 60MHz */
-    memory_region_init_io(&s->iomem, &sh7750_mem_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &sh7750_mem_ops, s,
                           "memory", 0x1fc01000);
 
-    memory_region_init_alias(&s->iomem_1f0, "memory-1f0",
+    memory_region_init_alias(&s->iomem_1f0, NULL, "memory-1f0",
                              &s->iomem, 0x1f000000, 0x1000);
     memory_region_add_subregion(sysmem, 0x1f000000, &s->iomem_1f0);
 
-    memory_region_init_alias(&s->iomem_ff0, "memory-ff0",
+    memory_region_init_alias(&s->iomem_ff0, NULL, "memory-ff0",
                              &s->iomem, 0x1f000000, 0x1000);
     memory_region_add_subregion(sysmem, 0xff000000, &s->iomem_ff0);
 
-    memory_region_init_alias(&s->iomem_1f8, "memory-1f8",
+    memory_region_init_alias(&s->iomem_1f8, NULL, "memory-1f8",
                              &s->iomem, 0x1f800000, 0x1000);
     memory_region_add_subregion(sysmem, 0x1f800000, &s->iomem_1f8);
 
-    memory_region_init_alias(&s->iomem_ff8, "memory-ff8",
+    memory_region_init_alias(&s->iomem_ff8, NULL, "memory-ff8",
                              &s->iomem, 0x1f800000, 0x1000);
     memory_region_add_subregion(sysmem, 0xff800000, &s->iomem_ff8);
 
-    memory_region_init_alias(&s->iomem_1fc, "memory-1fc",
+    memory_region_init_alias(&s->iomem_1fc, NULL, "memory-1fc",
                              &s->iomem, 0x1fc00000, 0x1000);
     memory_region_add_subregion(sysmem, 0x1fc00000, &s->iomem_1fc);
 
-    memory_region_init_alias(&s->iomem_ffc, "memory-ffc",
+    memory_region_init_alias(&s->iomem_ffc, NULL, "memory-ffc",
                              &s->iomem, 0x1fc00000, 0x1000);
     memory_region_add_subregion(sysmem, 0xffc00000, &s->iomem_ffc);
 
-    memory_region_init_io(&s->mmct_iomem, &sh7750_mmct_ops, s,
+    memory_region_init_io(&s->mmct_iomem, NULL, &sh7750_mmct_ops, s,
                           "cache-and-tlb", 0x08000000);
     memory_region_add_subregion(sysmem, 0xf0000000, &s->mmct_iomem);
 
diff --git a/hw/sh4/sh_pci.c b/hw/sh4/sh_pci.c
index d213a90580..8b842bc936 100644
--- a/hw/sh4/sh_pci.c
+++ b/hw/sh4/sh_pci.c
@@ -125,9 +125,9 @@ static int sh_pci_device_init(SysBusDevice *dev)
                               get_system_memory(),
                               get_system_io(),
                               PCI_DEVFN(0, 0), 4, TYPE_PCI_BUS);
-    memory_region_init_io(&s->memconfig_p4, &sh_pci_reg_ops, s,
+    memory_region_init_io(&s->memconfig_p4, NULL, &sh_pci_reg_ops, s,
                           "sh_pci", 0x224);
-    memory_region_init_alias(&s->memconfig_a7, "sh_pci.2", &s->memconfig_p4,
+    memory_region_init_alias(&s->memconfig_a7, NULL, "sh_pci.2", &s->memconfig_p4,
                              0, 0x224);
     isa_mmio_setup(&s->isa, 0x40000);
     sysbus_init_mmio(dev, &s->memconfig_p4);
diff --git a/hw/sh4/shix.c b/hw/sh4/shix.c
index ffac621a8c..84dd666bd5 100644
--- a/hw/sh4/shix.c
+++ b/hw/sh4/shix.c
@@ -59,16 +59,16 @@ static void shix_init(QEMUMachineInitArgs *args)
 
     /* Allocate memory space */
     printf("Allocating ROM\n");
-    memory_region_init_ram(rom, "shix.rom", 0x4000);
+    memory_region_init_ram(rom, NULL, "shix.rom", 0x4000);
     vmstate_register_ram_global(rom);
     memory_region_set_readonly(rom, true);
     memory_region_add_subregion(sysmem, 0x00000000, rom);
     printf("Allocating SDRAM 1\n");
-    memory_region_init_ram(&sdram[0], "shix.sdram1", 0x01000000);
+    memory_region_init_ram(&sdram[0], NULL, "shix.sdram1", 0x01000000);
     vmstate_register_ram_global(&sdram[0]);
     memory_region_add_subregion(sysmem, 0x08000000, &sdram[0]);
     printf("Allocating SDRAM 2\n");
-    memory_region_init_ram(&sdram[1], "shix.sdram2", 0x01000000);
+    memory_region_init_ram(&sdram[1], NULL, "shix.sdram2", 0x01000000);
     vmstate_register_ram_global(&sdram[1]);
     memory_region_add_subregion(sysmem, 0x0c000000, &sdram[1]);
 
diff --git a/hw/sparc/leon3.c b/hw/sparc/leon3.c
index 78c77eff46..5ef282fcda 100644
--- a/hw/sparc/leon3.c
+++ b/hw/sparc/leon3.c
@@ -147,13 +147,13 @@ static void leon3_generic_hw_init(QEMUMachineInitArgs *args)
         exit(1);
     }
 
-    memory_region_init_ram(ram, "leon3.ram", ram_size);
+    memory_region_init_ram(ram, NULL, "leon3.ram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space_mem, 0x40000000, ram);
 
     /* Allocate BIOS */
     prom_size = 8 * 1024 * 1024; /* 8Mb */
-    memory_region_init_ram(prom, "Leon3.bios", prom_size);
+    memory_region_init_ram(prom, NULL, "Leon3.bios", prom_size);
     vmstate_register_ram_global(prom);
     memory_region_set_readonly(prom, true);
     memory_region_add_subregion(address_space_mem, 0x00000000, prom);
diff --git a/hw/sparc/sun4m.c b/hw/sparc/sun4m.c
index 0e86ca765d..1a16c82cba 100644
--- a/hw/sparc/sun4m.c
+++ b/hw/sparc/sun4m.c
@@ -582,7 +582,7 @@ static int idreg_init1(SysBusDevice *dev)
 {
     IDRegState *s = FROM_SYSBUS(IDRegState, dev);
 
-    memory_region_init_ram(&s->mem, "sun4m.idreg", sizeof(idreg_data));
+    memory_region_init_ram(&s->mem, NULL, "sun4m.idreg", sizeof(idreg_data));
     vmstate_register_ram_global(&s->mem);
     memory_region_set_readonly(&s->mem, true);
     sysbus_init_mmio(dev, &s->mem);
@@ -625,7 +625,7 @@ static int afx_init1(SysBusDevice *dev)
 {
     AFXState *s = FROM_SYSBUS(AFXState, dev);
 
-    memory_region_init_ram(&s->mem, "sun4m.afx", 4);
+    memory_region_init_ram(&s->mem, NULL, "sun4m.afx", 4);
     vmstate_register_ram_global(&s->mem);
     sysbus_init_mmio(dev, &s->mem);
     return 0;
@@ -695,7 +695,7 @@ static int prom_init1(SysBusDevice *dev)
 {
     PROMState *s = FROM_SYSBUS(PROMState, dev);
 
-    memory_region_init_ram(&s->prom, "sun4m.prom", PROM_SIZE_MAX);
+    memory_region_init_ram(&s->prom, NULL, "sun4m.prom", PROM_SIZE_MAX);
     vmstate_register_ram_global(&s->prom);
     memory_region_set_readonly(&s->prom, true);
     sysbus_init_mmio(dev, &s->prom);
@@ -734,7 +734,7 @@ static int ram_init1(SysBusDevice *dev)
 {
     RamDevice *d = FROM_SYSBUS(RamDevice, dev);
 
-    memory_region_init_ram(&d->ram, "sun4m.ram", d->size);
+    memory_region_init_ram(&d->ram, NULL, "sun4m.ram", d->size);
     vmstate_register_ram_global(&d->ram);
     sysbus_init_mmio(dev, &d->ram);
     return 0;
diff --git a/hw/sparc64/sun4u.c b/hw/sparc64/sun4u.c
index a6a3b76a76..4643a8342a 100644
--- a/hw/sparc64/sun4u.c
+++ b/hw/sparc64/sun4u.c
@@ -680,7 +680,7 @@ static int prom_init1(SysBusDevice *dev)
 {
     PROMState *s = FROM_SYSBUS(PROMState, dev);
 
-    memory_region_init_ram(&s->prom, "sun4u.prom", PROM_SIZE_MAX);
+    memory_region_init_ram(&s->prom, NULL, "sun4u.prom", PROM_SIZE_MAX);
     vmstate_register_ram_global(&s->prom);
     memory_region_set_readonly(&s->prom, true);
     sysbus_init_mmio(dev, &s->prom);
@@ -720,7 +720,7 @@ static int ram_init1(SysBusDevice *dev)
 {
     RamDevice *d = FROM_SYSBUS(RamDevice, dev);
 
-    memory_region_init_ram(&d->ram, "sun4u.ram", d->size);
+    memory_region_init_ram(&d->ram, NULL, "sun4u.ram", d->size);
     vmstate_register_ram_global(&d->ram);
     sysbus_init_mmio(dev, &d->ram);
     return 0;
diff --git a/hw/ssi/omap_spi.c b/hw/ssi/omap_spi.c
index 11403c411b..0ed3b110e6 100644
--- a/hw/ssi/omap_spi.c
+++ b/hw/ssi/omap_spi.c
@@ -354,7 +354,7 @@ struct omap_mcspi_s *omap_mcspi_init(struct omap_target_agent_s *ta, int chnum,
     }
     omap_mcspi_reset(s);
 
-    memory_region_init_io(&s->iomem, &omap_mcspi_ops, s, "omap.mcspi",
+    memory_region_init_io(&s->iomem, NULL, &omap_mcspi_ops, s, "omap.mcspi",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &s->iomem);
 
diff --git a/hw/ssi/pl022.c b/hw/ssi/pl022.c
index 536c2166fe..ab569d6976 100644
--- a/hw/ssi/pl022.c
+++ b/hw/ssi/pl022.c
@@ -277,7 +277,7 @@ static int pl022_init(SysBusDevice *dev)
 {
     pl022_state *s = FROM_SYSBUS(pl022_state, dev);
 
-    memory_region_init_io(&s->iomem, &pl022_ops, s, "pl022", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl022_ops, s, "pl022", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     s->ssi = ssi_create_bus(&dev->qdev, "ssi");
diff --git a/hw/ssi/xilinx_spi.c b/hw/ssi/xilinx_spi.c
index f6bd3bac23..7a3c3560f6 100644
--- a/hw/ssi/xilinx_spi.c
+++ b/hw/ssi/xilinx_spi.c
@@ -330,7 +330,7 @@ static int xilinx_spi_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->cs_lines[i]);
     }
 
-    memory_region_init_io(&s->mmio, &spi_ops, s, "xilinx-spi", R_MAX * 4);
+    memory_region_init_io(&s->mmio, NULL, &spi_ops, s, "xilinx-spi", R_MAX * 4);
     sysbus_init_mmio(dev, &s->mmio);
 
     s->irqline = -1;
diff --git a/hw/ssi/xilinx_spips.c b/hw/ssi/xilinx_spips.c
index 05a3adaa90..d7b50748f5 100644
--- a/hw/ssi/xilinx_spips.c
+++ b/hw/ssi/xilinx_spips.c
@@ -663,7 +663,7 @@ static void xilinx_spips_realize(DeviceState *dev, Error **errp)
         sysbus_init_irq(sbd, &s->cs_lines[i]);
     }
 
-    memory_region_init_io(&s->iomem, xsc->reg_ops, s, "spi", R_MAX*4);
+    memory_region_init_io(&s->iomem, NULL, xsc->reg_ops, s, "spi", R_MAX*4);
     sysbus_init_mmio(sbd, &s->iomem);
 
     s->irqline = -1;
@@ -685,7 +685,7 @@ static void xilinx_qspips_realize(DeviceState *dev, Error **errp)
     s->num_txrx_bytes = 4;
 
     xilinx_spips_realize(dev, errp);
-    memory_region_init_io(&s->mmlqspi, &lqspi_ops, s, "lqspi",
+    memory_region_init_io(&s->mmlqspi, NULL, &lqspi_ops, s, "lqspi",
                           (1 << LQSPI_ADDRESS_BITS) * 2);
     sysbus_init_mmio(sbd, &s->mmlqspi);
 
diff --git a/hw/timer/arm_mptimer.c b/hw/timer/arm_mptimer.c
index 317f5e43ed..e78f820737 100644
--- a/hw/timer/arm_mptimer.c
+++ b/hw/timer/arm_mptimer.c
@@ -236,14 +236,14 @@ static int arm_mptimer_init(SysBusDevice *dev)
      *  * timer for core 1
      * and so on.
      */
-    memory_region_init_io(&s->iomem, &arm_thistimer_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &arm_thistimer_ops, s,
                           "arm_mptimer_timer", 0x20);
     sysbus_init_mmio(dev, &s->iomem);
     for (i = 0; i < s->num_cpu; i++) {
         TimerBlock *tb = &s->timerblock[i];
         tb->timer = qemu_new_timer_ns(vm_clock, timerblock_tick, tb);
         sysbus_init_irq(dev, &tb->irq);
-        memory_region_init_io(&tb->iomem, &timerblock_ops, tb,
+        memory_region_init_io(&tb->iomem, NULL, &timerblock_ops, tb,
                               "arm_mptimer_timerblock", 0x20);
         sysbus_init_mmio(dev, &tb->iomem);
     }
diff --git a/hw/timer/arm_timer.c b/hw/timer/arm_timer.c
index 644987046a..f1a501fbfa 100644
--- a/hw/timer/arm_timer.c
+++ b/hw/timer/arm_timer.c
@@ -284,7 +284,7 @@ static int sp804_init(SysBusDevice *dev)
     s->timer[1] = arm_timer_init(s->freq1);
     s->timer[0]->irq = qi[0];
     s->timer[1]->irq = qi[1];
-    memory_region_init_io(&s->iomem, &sp804_ops, s, "sp804", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &sp804_ops, s, "sp804", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     vmstate_register(&dev->qdev, -1, &vmstate_sp804, s);
     return 0;
@@ -347,7 +347,7 @@ static int icp_pit_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->timer[1]->irq);
     sysbus_init_irq(dev, &s->timer[2]->irq);
 
-    memory_region_init_io(&s->iomem, &icp_pit_ops, s, "icp_pit", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &icp_pit_ops, s, "icp_pit", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     /* This device has no state to save/restore.  The component timers will
        save themselves.  */
diff --git a/hw/timer/cadence_ttc.c b/hw/timer/cadence_ttc.c
index ba584f4719..4879cb09e0 100644
--- a/hw/timer/cadence_ttc.c
+++ b/hw/timer/cadence_ttc.c
@@ -409,7 +409,7 @@ static int cadence_ttc_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->timer[i].irq);
     }
 
-    memory_region_init_io(&s->iomem, &cadence_ttc_ops, s, "timer", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &cadence_ttc_ops, s, "timer", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
     return 0;
diff --git a/hw/timer/etraxfs_timer.c b/hw/timer/etraxfs_timer.c
index 3cd9476bb1..8a7b177ddd 100644
--- a/hw/timer/etraxfs_timer.c
+++ b/hw/timer/etraxfs_timer.c
@@ -323,7 +323,7 @@ static int etraxfs_timer_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &t->irq);
     sysbus_init_irq(dev, &t->nmi);
 
-    memory_region_init_io(&t->mmio, &timer_ops, t, "etraxfs-timer", 0x5c);
+    memory_region_init_io(&t->mmio, NULL, &timer_ops, t, "etraxfs-timer", 0x5c);
     sysbus_init_mmio(dev, &t->mmio);
     qemu_register_reset(etraxfs_timer_reset, t);
     return 0;
diff --git a/hw/timer/exynos4210_mct.c b/hw/timer/exynos4210_mct.c
index 38dcc1ac64..ba74d2b5aa 100644
--- a/hw/timer/exynos4210_mct.c
+++ b/hw/timer/exynos4210_mct.c
@@ -1449,7 +1449,7 @@ static int exynos4210_mct_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->l_timer[i].irq);
     }
 
-    memory_region_init_io(&s->iomem, &exynos4210_mct_ops, s, "exynos4210-mct",
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_mct_ops, s, "exynos4210-mct",
             MCT_SFR_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/timer/exynos4210_pwm.c b/hw/timer/exynos4210_pwm.c
index 185ccb9a74..62c42b4158 100644
--- a/hw/timer/exynos4210_pwm.c
+++ b/hw/timer/exynos4210_pwm.c
@@ -390,7 +390,7 @@ static int exynos4210_pwm_init(SysBusDevice *dev)
         s->timer[i].parent = s;
     }
 
-    memory_region_init_io(&s->iomem, &exynos4210_pwm_ops, s, "exynos4210-pwm",
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_pwm_ops, s, "exynos4210-pwm",
             EXYNOS4210_PWM_REG_MEM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/timer/exynos4210_rtc.c b/hw/timer/exynos4210_rtc.c
index 3ac77f9262..779dc77dc9 100644
--- a/hw/timer/exynos4210_rtc.c
+++ b/hw/timer/exynos4210_rtc.c
@@ -559,7 +559,7 @@ static int exynos4210_rtc_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->alm_irq);
     sysbus_init_irq(dev, &s->tick_irq);
 
-    memory_region_init_io(&s->iomem, &exynos4210_rtc_ops, s, "exynos4210-rtc",
+    memory_region_init_io(&s->iomem, NULL, &exynos4210_rtc_ops, s, "exynos4210-rtc",
             EXYNOS4210_RTC_REG_MEM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/timer/grlib_gptimer.c b/hw/timer/grlib_gptimer.c
index 7043a34684..749ed31dd7 100644
--- a/hw/timer/grlib_gptimer.c
+++ b/hw/timer/grlib_gptimer.c
@@ -365,7 +365,7 @@ static int grlib_gptimer_init(SysBusDevice *dev)
         ptimer_set_freq(timer->ptimer, unit->freq_hz);
     }
 
-    memory_region_init_io(&unit->iomem, &grlib_gptimer_ops, unit, "gptimer",
+    memory_region_init_io(&unit->iomem, NULL, &grlib_gptimer_ops, unit, "gptimer",
                           UNIT_REG_SIZE + GPTIMER_REG_SIZE * unit->nr_timers);
 
     sysbus_init_mmio(dev, &unit->iomem);
diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
index 95dd01d147..2e7fdb59b5 100644
--- a/hw/timer/hpet.c
+++ b/hw/timer/hpet.c
@@ -722,7 +722,7 @@ static int hpet_init(SysBusDevice *dev)
     qdev_init_gpio_out(&dev->qdev, &s->pit_enabled, 1);
 
     /* HPET Area */
-    memory_region_init_io(&s->iomem, &hpet_ram_ops, s, "hpet", 0x400);
+    memory_region_init_io(&s->iomem, NULL, &hpet_ram_ops, s, "hpet", 0x400);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
 }
diff --git a/hw/timer/i8254.c b/hw/timer/i8254.c
index 16c8dd687f..fdb23da635 100644
--- a/hw/timer/i8254.c
+++ b/hw/timer/i8254.c
@@ -333,7 +333,7 @@ static void pit_realizefn(DeviceState *dev, Error **err)
     s->irq_timer = qemu_new_timer_ns(vm_clock, pit_irq_timer, s);
     qdev_init_gpio_out(dev, &s->irq, 1);
 
-    memory_region_init_io(&pit->ioports, &pit_ioport_ops, pit, "pit", 4);
+    memory_region_init_io(&pit->ioports, NULL, &pit_ioport_ops, pit, "pit", 4);
 
     qdev_init_gpio_in(dev, pit_irq_control, 1);
 
diff --git a/hw/timer/imx_epit.c b/hw/timer/imx_epit.c
index 7cdb0060ab..d2e089507b 100644
--- a/hw/timer/imx_epit.c
+++ b/hw/timer/imx_epit.c
@@ -396,7 +396,7 @@ static void imx_epit_realize(DeviceState *dev, Error **errp)
     DPRINTF("\n");
 
     sysbus_init_irq(sbd, &s->irq);
-    memory_region_init_io(&s->iomem, &imx_epit_ops, s, TYPE_IMX_EPIT,
+    memory_region_init_io(&s->iomem, NULL, &imx_epit_ops, s, TYPE_IMX_EPIT,
                           0x00001000);
     sysbus_init_mmio(sbd, &s->iomem);
 
diff --git a/hw/timer/imx_gpt.c b/hw/timer/imx_gpt.c
index de53b13287..6e6442d462 100644
--- a/hw/timer/imx_gpt.c
+++ b/hw/timer/imx_gpt.c
@@ -514,7 +514,7 @@ static void imx_gpt_realize(DeviceState *dev, Error **errp)
     QEMUBH *bh;
 
     sysbus_init_irq(sbd, &s->irq);
-    memory_region_init_io(&s->iomem, &imx_gpt_ops, s, TYPE_IMX_GPT,
+    memory_region_init_io(&s->iomem, NULL, &imx_gpt_ops, s, TYPE_IMX_GPT,
                           0x00001000);
     sysbus_init_mmio(sbd, &s->iomem);
 
diff --git a/hw/timer/lm32_timer.c b/hw/timer/lm32_timer.c
index e06fac7082..2ab85886d2 100644
--- a/hw/timer/lm32_timer.c
+++ b/hw/timer/lm32_timer.c
@@ -180,7 +180,7 @@ static int lm32_timer_init(SysBusDevice *dev)
     s->ptimer = ptimer_init(s->bh);
     ptimer_set_freq(s->ptimer, s->freq_hz);
 
-    memory_region_init_io(&s->iomem, &timer_ops, s, "timer", R_MAX * 4);
+    memory_region_init_io(&s->iomem, NULL, &timer_ops, s, "timer", R_MAX * 4);
     sysbus_init_mmio(dev, &s->iomem);
 
     return 0;
diff --git a/hw/timer/m48t59.c b/hw/timer/m48t59.c
index bf6c4c876c..fdda6d6699 100644
--- a/hw/timer/m48t59.c
+++ b/hw/timer/m48t59.c
@@ -655,7 +655,7 @@ M48t59State *m48t59_init(qemu_irq IRQ, hwaddr mem_base,
     d = FROM_SYSBUS(M48t59SysBusState, s);
     state = &d->state;
     sysbus_connect_irq(s, 0, IRQ);
-    memory_region_init_io(&d->io, &m48t59_io_ops, state, "m48t59", 4);
+    memory_region_init_io(&d->io, NULL, &m48t59_io_ops, state, "m48t59", 4);
     if (io_base != 0) {
         memory_region_add_subregion(get_system_io(), io_base, &d->io);
     }
@@ -683,7 +683,7 @@ M48t59State *m48t59_init_isa(ISABus *bus, uint32_t io_base, uint16_t size,
     d = ISA_M48T59(isadev);
     s = &d->state;
 
-    memory_region_init_io(&d->io, &m48t59_io_ops, s, "m48t59", 4);
+    memory_region_init_io(&d->io, NULL, &m48t59_io_ops, s, "m48t59", 4);
     if (io_base != 0) {
         isa_register_ioport(isadev, &d->io, io_base);
     }
@@ -721,7 +721,7 @@ static int m48t59_init1(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->IRQ);
 
-    memory_region_init_io(&s->iomem, &nvram_ops, s, "m48t59.nvram", s->size);
+    memory_region_init_io(&s->iomem, NULL, &nvram_ops, s, "m48t59.nvram", s->size);
     sysbus_init_mmio(dev, &s->iomem);
     m48t59_realize_common(s, &err);
     if (err != NULL) {
diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
index 9c4a7bd074..4110a3794c 100644
--- a/hw/timer/mc146818rtc.c
+++ b/hw/timer/mc146818rtc.c
@@ -863,7 +863,7 @@ static void rtc_realizefn(DeviceState *dev, Error **errp)
     s->suspend_notifier.notify = rtc_notify_suspend;
     qemu_register_suspend_notifier(&s->suspend_notifier);
 
-    memory_region_init_io(&s->io, &cmos_ops, s, "rtc", 2);
+    memory_region_init_io(&s->io, NULL, &cmos_ops, s, "rtc", 2);
     isa_register_ioport(isadev, &s->io, base);
 
     qdev_set_legacy_instance_id(dev, base, 3);
diff --git a/hw/timer/milkymist-sysctl.c b/hw/timer/milkymist-sysctl.c
index e083a280c4..f253f218d7 100644
--- a/hw/timer/milkymist-sysctl.c
+++ b/hw/timer/milkymist-sysctl.c
@@ -280,7 +280,7 @@ static int milkymist_sysctl_init(SysBusDevice *dev)
     ptimer_set_freq(s->ptimer0, s->freq_hz);
     ptimer_set_freq(s->ptimer1, s->freq_hz);
 
-    memory_region_init_io(&s->regs_region, &sysctl_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, NULL, &sysctl_mmio_ops, s,
             "milkymist-sysctl", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
diff --git a/hw/timer/omap_gptimer.c b/hw/timer/omap_gptimer.c
index 9b0e9dd567..ac389d87ee 100644
--- a/hw/timer/omap_gptimer.c
+++ b/hw/timer/omap_gptimer.c
@@ -480,7 +480,7 @@ struct omap_gp_timer_s *omap_gp_timer_init(struct omap_target_agent_s *ta,
     omap_gp_timer_reset(s);
     omap_gp_timer_clk_setup(s);
 
-    memory_region_init_io(&s->iomem, &omap_gp_timer_ops, s, "omap.gptimer",
+    memory_region_init_io(&s->iomem, NULL, &omap_gp_timer_ops, s, "omap.gptimer",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &s->iomem);
 
diff --git a/hw/timer/omap_synctimer.c b/hw/timer/omap_synctimer.c
index a24f35c277..a12aca20df 100644
--- a/hw/timer/omap_synctimer.c
+++ b/hw/timer/omap_synctimer.c
@@ -94,7 +94,7 @@ struct omap_synctimer_s *omap_synctimer_init(struct omap_target_agent_s *ta,
     struct omap_synctimer_s *s = g_malloc0(sizeof(*s));
 
     omap_synctimer_reset(s);
-    memory_region_init_io(&s->iomem, &omap_synctimer_ops, s, "omap.synctimer",
+    memory_region_init_io(&s->iomem, NULL, &omap_synctimer_ops, s, "omap.synctimer",
                           omap_l4_region_size(ta, 0));
     omap_l4_attach(ta, 0, &s->iomem);
 
diff --git a/hw/timer/pl031.c b/hw/timer/pl031.c
index 764940be7e..cba4e8747f 100644
--- a/hw/timer/pl031.c
+++ b/hw/timer/pl031.c
@@ -192,7 +192,7 @@ static int pl031_init(SysBusDevice *dev)
     pl031_state *s = FROM_SYSBUS(pl031_state, dev);
     struct tm tm;
 
-    memory_region_init_io(&s->iomem, &pl031_ops, s, "pl031", 0x1000);
+    memory_region_init_io(&s->iomem, NULL, &pl031_ops, s, "pl031", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
     sysbus_init_irq(dev, &s->irq);
diff --git a/hw/timer/puv3_ost.c b/hw/timer/puv3_ost.c
index 0c3d827978..375d3684fb 100644
--- a/hw/timer/puv3_ost.c
+++ b/hw/timer/puv3_ost.c
@@ -122,7 +122,7 @@ static int puv3_ost_init(SysBusDevice *dev)
     s->ptimer = ptimer_init(s->bh);
     ptimer_set_freq(s->ptimer, 50 * 1000 * 1000);
 
-    memory_region_init_io(&s->iomem, &puv3_ost_ops, s, "puv3_ost",
+    memory_region_init_io(&s->iomem, NULL, &puv3_ost_ops, s, "puv3_ost",
             PUV3_REGS_OFFSET);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/timer/pxa2xx_timer.c b/hw/timer/pxa2xx_timer.c
index 8ea2416dd7..dd41a1033a 100644
--- a/hw/timer/pxa2xx_timer.c
+++ b/hw/timer/pxa2xx_timer.c
@@ -461,7 +461,7 @@ static int pxa2xx_timer_init(SysBusDevice *dev)
         }
     }
 
-    memory_region_init_io(&s->iomem, &pxa2xx_timer_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &pxa2xx_timer_ops, s,
                           "pxa2xx-timer", 0x00001000);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/timer/sh_timer.c b/hw/timer/sh_timer.c
index f92ff4f73f..251a10dbfa 100644
--- a/hw/timer/sh_timer.c
+++ b/hw/timer/sh_timer.c
@@ -319,14 +319,14 @@ void tmu012_init(MemoryRegion *sysmem, hwaddr base,
         s->timer[2] = sh_timer_init(freq, timer_feat | TIMER_FEAT_CAPT,
 				    ch2_irq0); /* ch2_irq1 not supported */
 
-    memory_region_init_io(&s->iomem, &tmu012_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &tmu012_ops, s,
                           "timer", 0x100000000ULL);
 
-    memory_region_init_alias(&s->iomem_p4, "timer-p4",
+    memory_region_init_alias(&s->iomem_p4, NULL, "timer-p4",
                              &s->iomem, 0, 0x1000);
     memory_region_add_subregion(sysmem, P4ADDR(base), &s->iomem_p4);
 
-    memory_region_init_alias(&s->iomem_a7, "timer-a7",
+    memory_region_init_alias(&s->iomem_a7, NULL, "timer-a7",
                              &s->iomem, 0, 0x1000);
     memory_region_add_subregion(sysmem, A7ADDR(base), &s->iomem_a7);
     /* ??? Save/restore.  */
diff --git a/hw/timer/slavio_timer.c b/hw/timer/slavio_timer.c
index 1145a87603..cad81a3801 100644
--- a/hw/timer/slavio_timer.c
+++ b/hw/timer/slavio_timer.c
@@ -394,7 +394,7 @@ static int slavio_timer_init1(SysBusDevice *dev)
 
         size = i == 0 ? SYS_TIMER_SIZE : CPU_TIMER_SIZE;
         snprintf(timer_name, sizeof(timer_name), "timer-%i", i);
-        memory_region_init_io(&tc->iomem, &slavio_timer_mem_ops, tc,
+        memory_region_init_io(&tc->iomem, NULL, &slavio_timer_mem_ops, tc,
                               timer_name, size);
         sysbus_init_mmio(dev, &tc->iomem);
 
diff --git a/hw/timer/tusb6010.c b/hw/timer/tusb6010.c
index 50edc063d1..fcce4ac8e5 100644
--- a/hw/timer/tusb6010.c
+++ b/hw/timer/tusb6010.c
@@ -779,7 +779,7 @@ static int tusb6010_init(SysBusDevice *dev)
     TUSBState *s = FROM_SYSBUS(TUSBState, dev);
     s->otg_timer = qemu_new_timer_ns(vm_clock, tusb_otg_tick, s);
     s->pwr_timer = qemu_new_timer_ns(vm_clock, tusb_power_tick, s);
-    memory_region_init_io(&s->iomem[1], &tusb_async_ops, s, "tusb-async",
+    memory_region_init_io(&s->iomem[1], NULL, &tusb_async_ops, s, "tusb-async",
                           UINT32_MAX);
     sysbus_init_mmio(dev, &s->iomem[0]);
     sysbus_init_mmio(dev, &s->iomem[1]);
diff --git a/hw/timer/xilinx_timer.c b/hw/timer/xilinx_timer.c
index 0c39cff089..f4b4fb5009 100644
--- a/hw/timer/xilinx_timer.c
+++ b/hw/timer/xilinx_timer.c
@@ -218,7 +218,7 @@ static int xilinx_timer_init(SysBusDevice *dev)
         ptimer_set_freq(xt->ptimer, t->freq_hz);
     }
 
-    memory_region_init_io(&t->mmio, &timer_ops, t, "xlnx.xps-timer",
+    memory_region_init_io(&t->mmio, NULL, &timer_ops, t, "xlnx.xps-timer",
                           R_MAX * 4 * num_timers(t));
     sysbus_init_mmio(dev, &t->mmio);
     return 0;
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index d4d8152875..5504fb4ce4 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -888,7 +888,7 @@ static void tpm_tis_initfn(Object *obj)
     ISADevice *dev = ISA_DEVICE(obj);
     TPMState *s = TPM(obj);
 
-    memory_region_init_io(&s->mmio, &tpm_tis_memory_ops, s, "tpm-tis-mmio",
+    memory_region_init_io(&s->mmio, NULL, &tpm_tis_memory_ops, s, "tpm-tis-mmio",
                           TPM_TIS_NUM_LOCALITIES << TPM_TIS_LOCALITY_SHIFT);
     memory_region_add_subregion(isa_address_space(dev), TPM_TIS_ADDR_BASE,
                                 &s->mmio);
diff --git a/hw/unicore32/puv3.c b/hw/unicore32/puv3.c
index 56d1afa4ff..5ff0dc9a07 100644
--- a/hw/unicore32/puv3.c
+++ b/hw/unicore32/puv3.c
@@ -73,7 +73,7 @@ static void puv3_board_init(CPUUniCore32State *env, ram_addr_t ram_size)
     MemoryRegion *ram_memory = g_new(MemoryRegion, 1);
 
     /* SDRAM at address zero.  */
-    memory_region_init_ram(ram_memory, "puv3.ram", ram_size);
+    memory_region_init_ram(ram_memory, NULL, "puv3.ram", ram_size);
     vmstate_register_ram_global(ram_memory);
     memory_region_add_subregion(get_system_memory(), 0, ram_memory);
 }
diff --git a/hw/usb/hcd-ehci-sysbus.c b/hw/usb/hcd-ehci-sysbus.c
index e7d4f74b82..76b4c05874 100644
--- a/hw/usb/hcd-ehci-sysbus.c
+++ b/hw/usb/hcd-ehci-sysbus.c
@@ -173,7 +173,7 @@ static void fusbh200_ehci_init(Object *obj)
     FUSBH200EHCIState *f = FUSBH200_EHCI(obj);
     EHCIState *s = &i->ehci;
 
-    memory_region_init_io(&f->mem_vendor, &fusbh200_ehci_mmio_ops, s,
+    memory_region_init_io(&f->mem_vendor, NULL, &fusbh200_ehci_mmio_ops, s,
                           "fusbh200", 0x4c);
     memory_region_add_subregion(&s->mem,
                                 s->opregbase + s->portscbase + 4 * s->portnr,
diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index f977a91366..440c4c2795 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -2553,12 +2553,12 @@ void usb_ehci_init(EHCIState *s, DeviceState *dev)
     QTAILQ_INIT(&s->pqueues);
     usb_packet_init(&s->ipacket);
 
-    memory_region_init(&s->mem, "ehci", MMIO_SIZE);
-    memory_region_init_io(&s->mem_caps, &ehci_mmio_caps_ops, s,
+    memory_region_init(&s->mem, NULL, "ehci", MMIO_SIZE);
+    memory_region_init_io(&s->mem_caps, NULL, &ehci_mmio_caps_ops, s,
                           "capabilities", CAPA_SIZE);
-    memory_region_init_io(&s->mem_opreg, &ehci_mmio_opreg_ops, s,
+    memory_region_init_io(&s->mem_opreg, NULL, &ehci_mmio_opreg_ops, s,
                           "operational", s->portscbase);
-    memory_region_init_io(&s->mem_ports, &ehci_mmio_port_ops, s,
+    memory_region_init_io(&s->mem_ports, NULL, &ehci_mmio_port_ops, s,
                           "ports", 4 * s->portnr);
 
     memory_region_add_subregion(&s->mem, s->capsbase, &s->mem_caps);
diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c
index 5513924138..aa51042c25 100644
--- a/hw/usb/hcd-ohci.c
+++ b/hw/usb/hcd-ohci.c
@@ -1830,7 +1830,7 @@ static int usb_ohci_init(OHCIState *ohci, DeviceState *dev,
         }
     }
 
-    memory_region_init_io(&ohci->mem, &ohci_mem_ops, ohci, "ohci", 256);
+    memory_region_init_io(&ohci->mem, NULL, &ohci_mem_ops, ohci, "ohci", 256);
     ohci->localmem_base = localmem_base;
 
     ohci->name = object_get_typename(OBJECT(dev));
diff --git a/hw/usb/hcd-uhci.c b/hw/usb/hcd-uhci.c
index c85b2038a2..502228bace 100644
--- a/hw/usb/hcd-uhci.c
+++ b/hw/usb/hcd-uhci.c
@@ -1259,7 +1259,7 @@ static int usb_uhci_common_initfn(PCIDevice *dev)
 
     qemu_register_reset(uhci_reset, s);
 
-    memory_region_init_io(&s->io_bar, &uhci_ioport_ops, s, "uhci", 0x20);
+    memory_region_init_io(&s->io_bar, NULL, &uhci_ioport_ops, s, "uhci", 0x20);
     /* Use region 4 for consistency with real hardware.  BSD guests seem
        to rely on this.  */
     pci_register_bar(&s->dev, 4, PCI_BASE_ADDRESS_SPACE_IO, &s->io_bar);
diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c
index 91633edbc6..493d759d6a 100644
--- a/hw/usb/hcd-xhci.c
+++ b/hw/usb/hcd-xhci.c
@@ -3342,14 +3342,14 @@ static int usb_xhci_initfn(struct PCIDevice *dev)
 
     xhci->irq = xhci->pci_dev.irq[0];
 
-    memory_region_init(&xhci->mem, "xhci", LEN_REGS);
-    memory_region_init_io(&xhci->mem_cap, &xhci_cap_ops, xhci,
+    memory_region_init(&xhci->mem, NULL, "xhci", LEN_REGS);
+    memory_region_init_io(&xhci->mem_cap, NULL, &xhci_cap_ops, xhci,
                           "capabilities", LEN_CAP);
-    memory_region_init_io(&xhci->mem_oper, &xhci_oper_ops, xhci,
+    memory_region_init_io(&xhci->mem_oper, NULL, &xhci_oper_ops, xhci,
                           "operational", 0x400);
-    memory_region_init_io(&xhci->mem_runtime, &xhci_runtime_ops, xhci,
+    memory_region_init_io(&xhci->mem_runtime, NULL, &xhci_runtime_ops, xhci,
                           "runtime", LEN_RUNTIME);
-    memory_region_init_io(&xhci->mem_doorbell, &xhci_doorbell_ops, xhci,
+    memory_region_init_io(&xhci->mem_doorbell, NULL, &xhci_doorbell_ops, xhci,
                           "doorbell", LEN_DOORBELL);
 
     memory_region_add_subregion(&xhci->mem, 0,            &xhci->mem_cap);
@@ -3361,7 +3361,7 @@ static int usb_xhci_initfn(struct PCIDevice *dev)
         XHCIPort *port = &xhci->ports[i];
         uint32_t offset = OFF_OPER + 0x400 + 0x10 * i;
         port->xhci = xhci;
-        memory_region_init_io(&port->mem, &xhci_port_ops, port,
+        memory_region_init_io(&port->mem, NULL, &xhci_port_ops, port,
                               port->name, 0x10);
         memory_region_add_subregion(&xhci->mem, offset, &port->mem);
     }
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index b070b6400b..c8ecc8eeaf 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -966,7 +966,7 @@ static void virtio_pci_device_plugged(DeviceState *d)
         size = 1 << qemu_fls(size);
     }
 
-    memory_region_init_io(&proxy->bar, &virtio_pci_config_ops, proxy,
+    memory_region_init_io(&proxy->bar, NULL, &virtio_pci_config_ops, proxy,
                           "virtio-pci", size);
     pci_register_bar(&proxy->pci_dev, 0, PCI_BASE_ADDRESS_SPACE_IO,
                      &proxy->bar);
diff --git a/hw/watchdog/wdt_i6300esb.c b/hw/watchdog/wdt_i6300esb.c
index 05af0b1b68..2c750144da 100644
--- a/hw/watchdog/wdt_i6300esb.c
+++ b/hw/watchdog/wdt_i6300esb.c
@@ -417,7 +417,7 @@ static int i6300esb_init(PCIDevice *dev)
     d->timer = qemu_new_timer_ns(vm_clock, i6300esb_timer_expired, d);
     d->previous_reboot_flag = 0;
 
-    memory_region_init_io(&d->io_mem, &i6300esb_ops, d, "i6300esb", 0x10);
+    memory_region_init_io(&d->io_mem, NULL, &i6300esb_ops, d, "i6300esb", 0x10);
     pci_register_bar(&d->dev, 0, 0, &d->io_mem);
     /* qemu_register_coalesced_mmio (addr, 0x10); ? */
 
diff --git a/hw/xen/xen_apic.c b/hw/xen/xen_apic.c
index a958782272..3526ffe621 100644
--- a/hw/xen/xen_apic.c
+++ b/hw/xen/xen_apic.c
@@ -38,7 +38,7 @@ static const MemoryRegionOps xen_apic_io_ops = {
 
 static void xen_apic_init(APICCommonState *s)
 {
-    memory_region_init_io(&s->io_memory, &xen_apic_io_ops, s, "xen-apic-msi",
+    memory_region_init_io(&s->io_memory, NULL, &xen_apic_io_ops, s, "xen-apic-msi",
                           APIC_SPACE_SIZE);
 
 #if defined(CONFIG_XEN_CTRL_INTERFACE_VERSION) \
diff --git a/hw/xen/xen_platform.c b/hw/xen/xen_platform.c
index f8f5dd5134..8855309e60 100644
--- a/hw/xen/xen_platform.c
+++ b/hw/xen/xen_platform.c
@@ -275,7 +275,7 @@ static const MemoryRegionOps platform_fixed_io_ops = {
 
 static void platform_fixed_ioport_init(PCIXenPlatformState* s)
 {
-    memory_region_init_io(&s->fixed_io, &platform_fixed_io_ops, s,
+    memory_region_init_io(&s->fixed_io, NULL, &platform_fixed_io_ops, s,
                           "xen-fixed", 16);
     memory_region_add_subregion(get_system_io(), XEN_PLATFORM_IOPORT,
                                 &s->fixed_io);
@@ -319,7 +319,7 @@ static const MemoryRegionOps xen_pci_io_ops = {
 
 static void platform_ioport_bar_setup(PCIXenPlatformState *d)
 {
-    memory_region_init_io(&d->bar, &xen_pci_io_ops, d, "xen-pci", 0x100);
+    memory_region_init_io(&d->bar, NULL, &xen_pci_io_ops, d, "xen-pci", 0x100);
 }
 
 static uint64_t platform_mmio_read(void *opaque, hwaddr addr,
@@ -347,7 +347,7 @@ static const MemoryRegionOps platform_mmio_handler = {
 
 static void platform_mmio_setup(PCIXenPlatformState *d)
 {
-    memory_region_init_io(&d->mmio_bar, &platform_mmio_handler, d,
+    memory_region_init_io(&d->mmio_bar, NULL, &platform_mmio_handler, d,
                           "xen-mmio", 0x1000000);
 }
 
diff --git a/hw/xen/xen_pt.c b/hw/xen/xen_pt.c
index c31a28a3a9..15b489620b 100644
--- a/hw/xen/xen_pt.c
+++ b/hw/xen/xen_pt.c
@@ -416,7 +416,7 @@ static int xen_pt_register_regions(XenPCIPassthroughState *s)
             }
         }
 
-        memory_region_init_io(&s->bar[i], &ops, &s->dev,
+        memory_region_init_io(&s->bar[i], NULL, &ops, &s->dev,
                               "xen-pci-pt-bar", r->size);
         pci_register_bar(&s->dev, i, type, &s->bar[i]);
 
@@ -440,7 +440,7 @@ static int xen_pt_register_regions(XenPCIPassthroughState *s)
 
         s->bases[PCI_ROM_SLOT].access.maddr = d->rom.base_addr;
 
-        memory_region_init_rom_device(&s->rom, NULL, NULL,
+        memory_region_init_rom_device(&s->rom, NULL, NULL, NULL,
                                       "xen-pci-pt-rom", d->rom.size);
         pci_register_bar(&s->dev, PCI_ROM_SLOT, PCI_BASE_ADDRESS_MEM_PREFETCH,
                          &s->rom);
diff --git a/hw/xen/xen_pt_msi.c b/hw/xen/xen_pt_msi.c
index db2c84237f..9c7d43b69e 100644
--- a/hw/xen/xen_pt_msi.c
+++ b/hw/xen/xen_pt_msi.c
@@ -544,7 +544,7 @@ int xen_pt_msix_init(XenPCIPassthroughState *s, uint32_t base)
         msix->msix_entry[i].pirq = XEN_PT_UNASSIGNED_PIRQ;
     }
 
-    memory_region_init_io(&msix->mmio, &pci_msix_ops, s, "xen-pci-pt-msix",
+    memory_region_init_io(&msix->mmio, NULL, &pci_msix_ops, s, "xen-pci-pt-msix",
                           (total_entries * PCI_MSIX_ENTRY_SIZE
                            + XC_PAGE_SIZE - 1)
                           & XC_PAGE_MASK);
diff --git a/hw/xtensa/xtensa_lx60.c b/hw/xtensa/xtensa_lx60.c
index 650dd31c98..11c30c2d1b 100644
--- a/hw/xtensa/xtensa_lx60.c
+++ b/hw/xtensa/xtensa_lx60.c
@@ -109,7 +109,7 @@ static Lx60FpgaState *lx60_fpga_init(MemoryRegion *address_space,
 {
     Lx60FpgaState *s = g_malloc(sizeof(Lx60FpgaState));
 
-    memory_region_init_io(&s->iomem, &lx60_fpga_ops, s,
+    memory_region_init_io(&s->iomem, NULL, &lx60_fpga_ops, s,
             "lx60.fpga", 0x10000);
     memory_region_add_subregion(address_space, base, &s->iomem);
     lx60_fpga_reset(s);
@@ -139,7 +139,7 @@ static void lx60_net_init(MemoryRegion *address_space,
             sysbus_mmio_get_region(s, 1));
 
     ram = g_malloc(sizeof(*ram));
-    memory_region_init_ram(ram, "open_eth.ram", 16384);
+    memory_region_init_ram(ram, NULL, "open_eth.ram", 16384);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(address_space, buffers, ram);
 }
@@ -195,12 +195,12 @@ static void lx_init(const LxBoardDesc *board, QEMUMachineInitArgs *args)
     }
 
     ram = g_malloc(sizeof(*ram));
-    memory_region_init_ram(ram, "lx60.dram", args->ram_size);
+    memory_region_init_ram(ram, NULL, "lx60.dram", args->ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(system_memory, 0, ram);
 
     system_io = g_malloc(sizeof(*system_io));
-    memory_region_init(system_io, "lx60.io", 224 * 1024 * 1024);
+    memory_region_init(system_io, NULL, "lx60.io", 224 * 1024 * 1024);
     memory_region_add_subregion(system_memory, 0xf0000000, system_io);
     lx60_fpga_init(system_io, 0x0d020000);
     if (nd_table[0].used) {
@@ -231,7 +231,7 @@ static void lx_init(const LxBoardDesc *board, QEMUMachineInitArgs *args)
     /* Use presence of kernel file name as 'boot from SRAM' switch. */
     if (kernel_filename) {
         rom = g_malloc(sizeof(*rom));
-        memory_region_init_ram(rom, "lx60.sram", board->sram_size);
+        memory_region_init_ram(rom, NULL, "lx60.sram", board->sram_size);
         vmstate_register_ram_global(rom);
         memory_region_add_subregion(system_memory, 0xfe000000, rom);
 
@@ -262,7 +262,7 @@ static void lx_init(const LxBoardDesc *board, QEMUMachineInitArgs *args)
             MemoryRegion *flash_mr = pflash_cfi01_get_memory(flash);
             MemoryRegion *flash_io = g_malloc(sizeof(*flash_io));
 
-            memory_region_init_alias(flash_io, "lx60.flash",
+            memory_region_init_alias(flash_io, NULL, "lx60.flash",
                     flash_mr, 0, board->flash_size);
             memory_region_add_subregion(system_memory, 0xfe000000,
                     flash_io);
diff --git a/hw/xtensa/xtensa_sim.c b/hw/xtensa/xtensa_sim.c
index 5241f8d734..a88707e161 100644
--- a/hw/xtensa/xtensa_sim.c
+++ b/hw/xtensa/xtensa_sim.c
@@ -75,12 +75,12 @@ static void xtensa_sim_init(QEMUMachineInitArgs *args)
     }
 
     ram = g_malloc(sizeof(*ram));
-    memory_region_init_ram(ram, "xtensa.sram", ram_size);
+    memory_region_init_ram(ram, NULL, "xtensa.sram", ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(get_system_memory(), 0, ram);
 
     rom = g_malloc(sizeof(*rom));
-    memory_region_init_ram(rom, "xtensa.rom", 0x1000);
+    memory_region_init_ram(rom, NULL, "xtensa.rom", 0x1000);
     vmstate_register_ram_global(rom);
     memory_region_add_subregion(get_system_memory(), 0xfe000000, rom);