accel: move kvm related accelerator files into accel/

move kvm related accelerator files into accel/ subdirectory, also
create one stub subdirectory, which will include accelerator's stub
files.

Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <1496383606-18060-5-git-send-email-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

6 files changed, 2810 insertions, 0 deletions

diff --git a/accel/Makefile.objs b/accel/Makefile.objs
index 11ad823609..cd5702f347 100644
--- a/accel/Makefile.objs
+++ b/accel/Makefile.objs
@@ -1,2 +1,4 @@
 obj-$(CONFIG_SOFTMMU) += accel.o
+obj-y += kvm/
 obj-y += tcg/
+obj-y += stubs/
diff --git a/accel/kvm/Makefile.objs b/accel/kvm/Makefile.objs
new file mode 100644
index 0000000000..85351e7de7
--- /dev/null
+++ b/accel/kvm/Makefile.objs
@@ -0,0 +1 @@
+obj-$(CONFIG_KVM) += kvm-all.o
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
new file mode 100644
index 0000000000..75feffa504
--- /dev/null
+++ b/accel/kvm/kvm-all.c
@@ -0,0 +1,2633 @@
+/*
+ * QEMU KVM support
+ *
+ * Copyright IBM, Corp. 2008
+ *           Red Hat, Inc. 2008
+ *
+ * Authors:
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *  Glauber Costa     <gcosta@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include <sys/ioctl.h>
+
+#include <linux/kvm.h>
+
+#include "qemu-common.h"
+#include "qemu/atomic.h"
+#include "qemu/option.h"
+#include "qemu/config-file.h"
+#include "qemu/error-report.h"
+#include "qapi/error.h"
+#include "hw/hw.h"
+#include "hw/pci/msi.h"
+#include "hw/pci/msix.h"
+#include "hw/s390x/adapter.h"
+#include "exec/gdbstub.h"
+#include "sysemu/kvm_int.h"
+#include "sysemu/cpus.h"
+#include "qemu/bswap.h"
+#include "exec/memory.h"
+#include "exec/ram_addr.h"
+#include "exec/address-spaces.h"
+#include "qemu/event_notifier.h"
+#include "trace.h"
+#include "hw/irq.h"
+
+#include "hw/boards.h"
+
+/* This check must be after config-host.h is included */
+#ifdef CONFIG_EVENTFD
+#include <sys/eventfd.h>
+#endif
+
+/* KVM uses PAGE_SIZE in its definition of KVM_COALESCED_MMIO_MAX. We
+ * need to use the real host PAGE_SIZE, as that's what KVM will use.
+ */
+#define PAGE_SIZE getpagesize()
+
+//#define DEBUG_KVM
+
+#ifdef DEBUG_KVM
+#define DPRINTF(fmt, ...) \
+    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+    do { } while (0)
+#endif
+
+#define KVM_MSI_HASHTAB_SIZE    256
+
+struct KVMParkedVcpu {
+    unsigned long vcpu_id;
+    int kvm_fd;
+    QLIST_ENTRY(KVMParkedVcpu) node;
+};
+
+struct KVMState
+{
+    AccelState parent_obj;
+
+    int nr_slots;
+    int fd;
+    int vmfd;
+    int coalesced_mmio;
+    struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
+    bool coalesced_flush_in_progress;
+    int broken_set_mem_region;
+    int vcpu_events;
+    int robust_singlestep;
+    int debugregs;
+#ifdef KVM_CAP_SET_GUEST_DEBUG
+    struct kvm_sw_breakpoint_head kvm_sw_breakpoints;
+#endif
+    int many_ioeventfds;
+    int intx_set_mask;
+    /* The man page (and posix) say ioctl numbers are signed int, but
+     * they're not.  Linux, glibc and *BSD all treat ioctl numbers as
+     * unsigned, and treating them as signed here can break things */
+    unsigned irq_set_ioctl;
+    unsigned int sigmask_len;
+    GHashTable *gsimap;
+#ifdef KVM_CAP_IRQ_ROUTING
+    struct kvm_irq_routing *irq_routes;
+    int nr_allocated_irq_routes;
+    unsigned long *used_gsi_bitmap;
+    unsigned int gsi_count;
+    QTAILQ_HEAD(msi_hashtab, KVMMSIRoute) msi_hashtab[KVM_MSI_HASHTAB_SIZE];
+#endif
+    KVMMemoryListener memory_listener;
+    QLIST_HEAD(, KVMParkedVcpu) kvm_parked_vcpus;
+};
+
+KVMState *kvm_state;
+bool kvm_kernel_irqchip;
+bool kvm_split_irqchip;
+bool kvm_async_interrupts_allowed;
+bool kvm_halt_in_kernel_allowed;
+bool kvm_eventfds_allowed;
+bool kvm_irqfds_allowed;
+bool kvm_resamplefds_allowed;
+bool kvm_msi_via_irqfd_allowed;
+bool kvm_gsi_routing_allowed;
+bool kvm_gsi_direct_mapping;
+bool kvm_allowed;
+bool kvm_readonly_mem_allowed;
+bool kvm_vm_attributes_allowed;
+bool kvm_direct_msi_allowed;
+bool kvm_ioeventfd_any_length_allowed;
+bool kvm_msi_use_devid;
+static bool kvm_immediate_exit;
+
+static const KVMCapabilityInfo kvm_required_capabilites[] = {
+    KVM_CAP_INFO(USER_MEMORY),
+    KVM_CAP_INFO(DESTROY_MEMORY_REGION_WORKS),
+    KVM_CAP_LAST_INFO
+};
+
+int kvm_get_max_memslots(void)
+{
+    KVMState *s = KVM_STATE(current_machine->accelerator);
+
+    return s->nr_slots;
+}
+
+static KVMSlot *kvm_get_free_slot(KVMMemoryListener *kml)
+{
+    KVMState *s = kvm_state;
+    int i;
+
+    for (i = 0; i < s->nr_slots; i++) {
+        if (kml->slots[i].memory_size == 0) {
+            return &kml->slots[i];
+        }
+    }
+
+    return NULL;
+}
+
+bool kvm_has_free_slot(MachineState *ms)
+{
+    KVMState *s = KVM_STATE(ms->accelerator);
+
+    return kvm_get_free_slot(&s->memory_listener);
+}
+
+static KVMSlot *kvm_alloc_slot(KVMMemoryListener *kml)
+{
+    KVMSlot *slot = kvm_get_free_slot(kml);
+
+    if (slot) {
+        return slot;
+    }
+
+    fprintf(stderr, "%s: no free slot available\n", __func__);
+    abort();
+}
+
+static KVMSlot *kvm_lookup_matching_slot(KVMMemoryListener *kml,
+                                         hwaddr start_addr,
+                                         hwaddr end_addr)
+{
+    KVMState *s = kvm_state;
+    int i;
+
+    for (i = 0; i < s->nr_slots; i++) {
+        KVMSlot *mem = &kml->slots[i];
+
+        if (start_addr == mem->start_addr &&
+            end_addr == mem->start_addr + mem->memory_size) {
+            return mem;
+        }
+    }
+
+    return NULL;
+}
+
+/*
+ * Find overlapping slot with lowest start address
+ */
+static KVMSlot *kvm_lookup_overlapping_slot(KVMMemoryListener *kml,
+                                            hwaddr start_addr,
+                                            hwaddr end_addr)
+{
+    KVMState *s = kvm_state;
+    KVMSlot *found = NULL;
+    int i;
+
+    for (i = 0; i < s->nr_slots; i++) {
+        KVMSlot *mem = &kml->slots[i];
+
+        if (mem->memory_size == 0 ||
+            (found && found->start_addr < mem->start_addr)) {
+            continue;
+        }
+
+        if (end_addr > mem->start_addr &&
+            start_addr < mem->start_addr + mem->memory_size) {
+            found = mem;
+        }
+    }
+
+    return found;
+}
+
+int kvm_physical_memory_addr_from_host(KVMState *s, void *ram,
+                                       hwaddr *phys_addr)
+{
+    KVMMemoryListener *kml = &s->memory_listener;
+    int i;
+
+    for (i = 0; i < s->nr_slots; i++) {
+        KVMSlot *mem = &kml->slots[i];
+
+        if (ram >= mem->ram && ram < mem->ram + mem->memory_size) {
+            *phys_addr = mem->start_addr + (ram - mem->ram);
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
+static int kvm_set_user_memory_region(KVMMemoryListener *kml, KVMSlot *slot)
+{
+    KVMState *s = kvm_state;
+    struct kvm_userspace_memory_region mem;
+
+    mem.slot = slot->slot | (kml->as_id << 16);
+    mem.guest_phys_addr = slot->start_addr;
+    mem.userspace_addr = (unsigned long)slot->ram;
+    mem.flags = slot->flags;
+
+    if (slot->memory_size && mem.flags & KVM_MEM_READONLY) {
+        /* Set the slot size to 0 before setting the slot to the desired
+         * value. This is needed based on KVM commit 75d61fbc. */
+        mem.memory_size = 0;
+        kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
+    }
+    mem.memory_size = slot->memory_size;
+    return kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
+}
+
+int kvm_destroy_vcpu(CPUState *cpu)
+{
+    KVMState *s = kvm_state;
+    long mmap_size;
+    struct KVMParkedVcpu *vcpu = NULL;
+    int ret = 0;
+
+    DPRINTF("kvm_destroy_vcpu\n");
+
+    mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
+    if (mmap_size < 0) {
+        ret = mmap_size;
+        DPRINTF("KVM_GET_VCPU_MMAP_SIZE failed\n");
+        goto err;
+    }
+
+    ret = munmap(cpu->kvm_run, mmap_size);
+    if (ret < 0) {
+        goto err;
+    }
+
+    vcpu = g_malloc0(sizeof(*vcpu));
+    vcpu->vcpu_id = kvm_arch_vcpu_id(cpu);
+    vcpu->kvm_fd = cpu->kvm_fd;
+    QLIST_INSERT_HEAD(&kvm_state->kvm_parked_vcpus, vcpu, node);
+err:
+    return ret;
+}
+
+static int kvm_get_vcpu(KVMState *s, unsigned long vcpu_id)
+{
+    struct KVMParkedVcpu *cpu;
+
+    QLIST_FOREACH(cpu, &s->kvm_parked_vcpus, node) {
+        if (cpu->vcpu_id == vcpu_id) {
+            int kvm_fd;
+
+            QLIST_REMOVE(cpu, node);
+            kvm_fd = cpu->kvm_fd;
+            g_free(cpu);
+            return kvm_fd;
+        }
+    }
+
+    return kvm_vm_ioctl(s, KVM_CREATE_VCPU, (void *)vcpu_id);
+}
+
+int kvm_init_vcpu(CPUState *cpu)
+{
+    KVMState *s = kvm_state;
+    long mmap_size;
+    int ret;
+
+    DPRINTF("kvm_init_vcpu\n");
+
+    ret = kvm_get_vcpu(s, kvm_arch_vcpu_id(cpu));
+    if (ret < 0) {
+        DPRINTF("kvm_create_vcpu failed\n");
+        goto err;
+    }
+
+    cpu->kvm_fd = ret;
+    cpu->kvm_state = s;
+    cpu->kvm_vcpu_dirty = true;
+
+    mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
+    if (mmap_size < 0) {
+        ret = mmap_size;
+        DPRINTF("KVM_GET_VCPU_MMAP_SIZE failed\n");
+        goto err;
+    }
+
+    cpu->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
+                        cpu->kvm_fd, 0);
+    if (cpu->kvm_run == MAP_FAILED) {
+        ret = -errno;
+        DPRINTF("mmap'ing vcpu state failed\n");
+        goto err;
+    }
+
+    if (s->coalesced_mmio && !s->coalesced_mmio_ring) {
+        s->coalesced_mmio_ring =
+            (void *)cpu->kvm_run + s->coalesced_mmio * PAGE_SIZE;
+    }
+
+    ret = kvm_arch_init_vcpu(cpu);
+err:
+    return ret;
+}
+
+/*
+ * dirty pages logging control
+ */
+
+static int kvm_mem_flags(MemoryRegion *mr)
+{
+    bool readonly = mr->readonly || memory_region_is_romd(mr);
+    int flags = 0;
+
+    if (memory_region_get_dirty_log_mask(mr) != 0) {
+        flags |= KVM_MEM_LOG_DIRTY_PAGES;
+    }
+    if (readonly && kvm_readonly_mem_allowed) {
+        flags |= KVM_MEM_READONLY;
+    }
+    return flags;
+}
+
+static int kvm_slot_update_flags(KVMMemoryListener *kml, KVMSlot *mem,
+                                 MemoryRegion *mr)
+{
+    int old_flags;
+
+    old_flags = mem->flags;
+    mem->flags = kvm_mem_flags(mr);
+
+    /* If nothing changed effectively, no need to issue ioctl */
+    if (mem->flags == old_flags) {
+        return 0;
+    }
+
+    return kvm_set_user_memory_region(kml, mem);
+}
+
+static int kvm_section_update_flags(KVMMemoryListener *kml,
+                                    MemoryRegionSection *section)
+{
+    hwaddr phys_addr = section->offset_within_address_space;
+    ram_addr_t size = int128_get64(section->size);
+    KVMSlot *mem = kvm_lookup_matching_slot(kml, phys_addr, phys_addr + size);
+
+    if (mem == NULL)  {
+        return 0;
+    } else {
+        return kvm_slot_update_flags(kml, mem, section->mr);
+    }
+}
+
+static void kvm_log_start(MemoryListener *listener,
+                          MemoryRegionSection *section,
+                          int old, int new)
+{
+    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
+    int r;
+
+    if (old != 0) {
+        return;
+    }
+
+    r = kvm_section_update_flags(kml, section);
+    if (r < 0) {
+        abort();
+    }
+}
+
+static void kvm_log_stop(MemoryListener *listener,
+                          MemoryRegionSection *section,
+                          int old, int new)
+{
+    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
+    int r;
+
+    if (new != 0) {
+        return;
+    }
+
+    r = kvm_section_update_flags(kml, section);
+    if (r < 0) {
+        abort();
+    }
+}
+
+/* get kvm's dirty pages bitmap and update qemu's */
+static int kvm_get_dirty_pages_log_range(MemoryRegionSection *section,
+                                         unsigned long *bitmap)
+{
+    ram_addr_t start = section->offset_within_region +
+                       memory_region_get_ram_addr(section->mr);
+    ram_addr_t pages = int128_get64(section->size) / getpagesize();
+
+    cpu_physical_memory_set_dirty_lebitmap(bitmap, start, pages);
+    return 0;
+}
+
+#define ALIGN(x, y)  (((x)+(y)-1) & ~((y)-1))
+
+/**
+ * kvm_physical_sync_dirty_bitmap - Grab dirty bitmap from kernel space
+ * This function updates qemu's dirty bitmap using
+ * memory_region_set_dirty().  This means all bits are set
+ * to dirty.
+ *
+ * @start_add: start of logged region.
+ * @end_addr: end of logged region.
+ */
+static int kvm_physical_sync_dirty_bitmap(KVMMemoryListener *kml,
+                                          MemoryRegionSection *section)
+{
+    KVMState *s = kvm_state;
+    unsigned long size, allocated_size = 0;
+    struct kvm_dirty_log d = {};
+    KVMSlot *mem;
+    int ret = 0;
+    hwaddr start_addr = section->offset_within_address_space;
+    hwaddr end_addr = start_addr + int128_get64(section->size);
+
+    d.dirty_bitmap = NULL;
+    while (start_addr < end_addr) {
+        mem = kvm_lookup_overlapping_slot(kml, start_addr, end_addr);
+        if (mem == NULL) {
+            break;
+        }
+
+        /* XXX bad kernel interface alert
+         * For dirty bitmap, kernel allocates array of size aligned to
+         * bits-per-long.  But for case when the kernel is 64bits and
+         * the userspace is 32bits, userspace can't align to the same
+         * bits-per-long, since sizeof(long) is different between kernel
+         * and user space.  This way, userspace will provide buffer which
+         * may be 4 bytes less than the kernel will use, resulting in
+         * userspace memory corruption (which is not detectable by valgrind
+         * too, in most cases).
+         * So for now, let's align to 64 instead of HOST_LONG_BITS here, in
+         * a hope that sizeof(long) won't become >8 any time soon.
+         */
+        size = ALIGN(((mem->memory_size) >> TARGET_PAGE_BITS),
+                     /*HOST_LONG_BITS*/ 64) / 8;
+        if (!d.dirty_bitmap) {
+            d.dirty_bitmap = g_malloc(size);
+        } else if (size > allocated_size) {
+            d.dirty_bitmap = g_realloc(d.dirty_bitmap, size);
+        }
+        allocated_size = size;
+        memset(d.dirty_bitmap, 0, allocated_size);
+
+        d.slot = mem->slot | (kml->as_id << 16);
+        if (kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d) == -1) {
+            DPRINTF("ioctl failed %d\n", errno);
+            ret = -1;
+            break;
+        }
+
+        kvm_get_dirty_pages_log_range(section, d.dirty_bitmap);
+        start_addr = mem->start_addr + mem->memory_size;
+    }
+    g_free(d.dirty_bitmap);
+
+    return ret;
+}
+
+static void kvm_coalesce_mmio_region(MemoryListener *listener,
+                                     MemoryRegionSection *secion,
+                                     hwaddr start, hwaddr size)
+{
+    KVMState *s = kvm_state;
+
+    if (s->coalesced_mmio) {
+        struct kvm_coalesced_mmio_zone zone;
+
+        zone.addr = start;
+        zone.size = size;
+        zone.pad = 0;
+
+        (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
+    }
+}
+
+static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
+                                       MemoryRegionSection *secion,
+                                       hwaddr start, hwaddr size)
+{
+    KVMState *s = kvm_state;
+
+    if (s->coalesced_mmio) {
+        struct kvm_coalesced_mmio_zone zone;
+
+        zone.addr = start;
+        zone.size = size;
+        zone.pad = 0;
+
+        (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
+    }
+}
+
+int kvm_check_extension(KVMState *s, unsigned int extension)
+{
+    int ret;
+
+    ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, extension);
+    if (ret < 0) {
+        ret = 0;
+    }
+
+    return ret;
+}
+
+int kvm_vm_check_extension(KVMState *s, unsigned int extension)
+{
+    int ret;
+
+    ret = kvm_vm_ioctl(s, KVM_CHECK_EXTENSION, extension);
+    if (ret < 0) {
+        /* VM wide version not implemented, use global one instead */
+        ret = kvm_check_extension(s, extension);
+    }
+
+    return ret;
+}
+
+static uint32_t adjust_ioeventfd_endianness(uint32_t val, uint32_t size)
+{
+#if defined(HOST_WORDS_BIGENDIAN) != defined(TARGET_WORDS_BIGENDIAN)
+    /* The kernel expects ioeventfd values in HOST_WORDS_BIGENDIAN
+     * endianness, but the memory core hands them in target endianness.
+     * For example, PPC is always treated as big-endian even if running
+     * on KVM and on PPC64LE.  Correct here.
+     */
+    switch (size) {
+    case 2:
+        val = bswap16(val);
+        break;
+    case 4:
+        val = bswap32(val);
+        break;
+    }
+#endif
+    return val;
+}
+
+static int kvm_set_ioeventfd_mmio(int fd, hwaddr addr, uint32_t val,
+                                  bool assign, uint32_t size, bool datamatch)
+{
+    int ret;
+    struct kvm_ioeventfd iofd = {
+        .datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0,
+        .addr = addr,
+        .len = size,
+        .flags = 0,
+        .fd = fd,
+    };
+
+    if (!kvm_enabled()) {
+        return -ENOSYS;
+    }
+
+    if (datamatch) {
+        iofd.flags |= KVM_IOEVENTFD_FLAG_DATAMATCH;
+    }
+    if (!assign) {
+        iofd.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
+    }
+
+    ret = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &iofd);
+
+    if (ret < 0) {
+        return -errno;
+    }
+
+    return 0;
+}
+
+static int kvm_set_ioeventfd_pio(int fd, uint16_t addr, uint16_t val,
+                                 bool assign, uint32_t size, bool datamatch)
+{
+    struct kvm_ioeventfd kick = {
+        .datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0,
+        .addr = addr,
+        .flags = KVM_IOEVENTFD_FLAG_PIO,
+        .len = size,
+        .fd = fd,
+    };
+    int r;
+    if (!kvm_enabled()) {
+        return -ENOSYS;
+    }
+    if (datamatch) {
+        kick.flags |= KVM_IOEVENTFD_FLAG_DATAMATCH;
+    }
+    if (!assign) {
+        kick.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
+    }
+    r = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &kick);
+    if (r < 0) {
+        return r;
+    }
+    return 0;
+}
+
+
+static int kvm_check_many_ioeventfds(void)
+{
+    /* Userspace can use ioeventfd for io notification.  This requires a host
+     * that supports eventfd(2) and an I/O thread; since eventfd does not
+     * support SIGIO it cannot interrupt the vcpu.
+     *
+     * Older kernels have a 6 device limit on the KVM io bus.  Find out so we
+     * can avoid creating too many ioeventfds.
+     */
+#if defined(CONFIG_EVENTFD)
+    int ioeventfds[7];
+    int i, ret = 0;
+    for (i = 0; i < ARRAY_SIZE(ioeventfds); i++) {
+        ioeventfds[i] = eventfd(0, EFD_CLOEXEC);
+        if (ioeventfds[i] < 0) {
+            break;
+        }
+        ret = kvm_set_ioeventfd_pio(ioeventfds[i], 0, i, true, 2, true);
+        if (ret < 0) {
+            close(ioeventfds[i]);
+            break;
+        }
+    }
+
+    /* Decide whether many devices are supported or not */
+    ret = i == ARRAY_SIZE(ioeventfds);
+
+    while (i-- > 0) {
+        kvm_set_ioeventfd_pio(ioeventfds[i], 0, i, false, 2, true);
+        close(ioeventfds[i]);
+    }
+    return ret;
+#else
+    return 0;
+#endif
+}
+
+static const KVMCapabilityInfo *
+kvm_check_extension_list(KVMState *s, const KVMCapabilityInfo *list)
+{
+    while (list->name) {
+        if (!kvm_check_extension(s, list->value)) {
+            return list;
+        }
+        list++;
+    }
+    return NULL;
+}
+
+static void kvm_set_phys_mem(KVMMemoryListener *kml,
+                             MemoryRegionSection *section, bool add)
+{
+    KVMState *s = kvm_state;
+    KVMSlot *mem, old;
+    int err;
+    MemoryRegion *mr = section->mr;
+    bool writeable = !mr->readonly && !mr->rom_device;
+    hwaddr start_addr = section->offset_within_address_space;
+    ram_addr_t size = int128_get64(section->size);
+    void *ram = NULL;
+    unsigned delta;
+
+    /* kvm works in page size chunks, but the function may be called
+       with sub-page size and unaligned start address. Pad the start
+       address to next and truncate size to previous page boundary. */
+    delta = qemu_real_host_page_size - (start_addr & ~qemu_real_host_page_mask);
+    delta &= ~qemu_real_host_page_mask;
+    if (delta > size) {
+        return;
+    }
+    start_addr += delta;
+    size -= delta;
+    size &= qemu_real_host_page_mask;
+    if (!size || (start_addr & ~qemu_real_host_page_mask)) {
+        return;
+    }
+
+    if (!memory_region_is_ram(mr)) {
+        if (writeable || !kvm_readonly_mem_allowed) {
+            return;
+        } else if (!mr->romd_mode) {
+            /* If the memory device is not in romd_mode, then we actually want
+             * to remove the kvm memory slot so all accesses will trap. */
+            add = false;
+        }
+    }
+
+    ram = memory_region_get_ram_ptr(mr) + section->offset_within_region + delta;
+
+    while (1) {
+        mem = kvm_lookup_overlapping_slot(kml, start_addr, start_addr + size);
+        if (!mem) {
+            break;
+        }
+
+        if (add && start_addr >= mem->start_addr &&
+            (start_addr + size <= mem->start_addr + mem->memory_size) &&
+            (ram - start_addr == mem->ram - mem->start_addr)) {
+            /* The new slot fits into the existing one and comes with
+             * identical parameters - update flags and done. */
+            kvm_slot_update_flags(kml, mem, mr);
+            return;
+        }
+
+        old = *mem;
+
+        if (mem->flags & KVM_MEM_LOG_DIRTY_PAGES) {
+            kvm_physical_sync_dirty_bitmap(kml, section);
+        }
+
+        /* unregister the overlapping slot */
+        mem->memory_size = 0;
+        err = kvm_set_user_memory_region(kml, mem);
+        if (err) {
+            fprintf(stderr, "%s: error unregistering overlapping slot: %s\n",
+                    __func__, strerror(-err));
+            abort();
+        }
+
+        /* Workaround for older KVM versions: we can't join slots, even not by
+         * unregistering the previous ones and then registering the larger
+         * slot. We have to maintain the existing fragmentation. Sigh.
+         *
+         * This workaround assumes that the new slot starts at the same
+         * address as the first existing one. If not or if some overlapping
+         * slot comes around later, we will fail (not seen in practice so far)
+         * - and actually require a recent KVM version. */
+        if (s->broken_set_mem_region &&
+            old.start_addr == start_addr && old.memory_size < size && add) {
+            mem = kvm_alloc_slot(kml);
+            mem->memory_size = old.memory_size;
+            mem->start_addr = old.start_addr;
+            mem->ram = old.ram;
+            mem->flags = kvm_mem_flags(mr);
+
+            err = kvm_set_user_memory_region(kml, mem);
+            if (err) {
+                fprintf(stderr, "%s: error updating slot: %s\n", __func__,
+                        strerror(-err));
+                abort();
+            }
+
+            start_addr += old.memory_size;
+            ram += old.memory_size;
+            size -= old.memory_size;
+            continue;
+        }
+
+        /* register prefix slot */
+        if (old.start_addr < start_addr) {
+            mem = kvm_alloc_slot(kml);
+            mem->memory_size = start_addr - old.start_addr;
+            mem->start_addr = old.start_addr;
+            mem->ram = old.ram;
+            mem->flags =  kvm_mem_flags(mr);
+
+            err = kvm_set_user_memory_region(kml, mem);
+            if (err) {
+                fprintf(stderr, "%s: error registering prefix slot: %s\n",
+                        __func__, strerror(-err));
+#ifdef TARGET_PPC
+                fprintf(stderr, "%s: This is probably because your kernel's " \
+                                "PAGE_SIZE is too big. Please try to use 4k " \
+                                "PAGE_SIZE!\n", __func__);
+#endif
+                abort();
+            }
+        }
+
+        /* register suffix slot */
+        if (old.start_addr + old.memory_size > start_addr + size) {
+            ram_addr_t size_delta;
+
+            mem = kvm_alloc_slot(kml);
+            mem->start_addr = start_addr + size;
+            size_delta = mem->start_addr - old.start_addr;
+            mem->memory_size = old.memory_size - size_delta;
+            mem->ram = old.ram + size_delta;
+            mem->flags = kvm_mem_flags(mr);
+
+            err = kvm_set_user_memory_region(kml, mem);
+            if (err) {
+                fprintf(stderr, "%s: error registering suffix slot: %s\n",
+                        __func__, strerror(-err));
+                abort();
+            }
+        }
+    }
+
+    /* in case the KVM bug workaround already "consumed" the new slot */
+    if (!size) {
+        return;
+    }
+    if (!add) {
+        return;
+    }
+    mem = kvm_alloc_slot(kml);
+    mem->memory_size = size;
+    mem->start_addr = start_addr;
+    mem->ram = ram;
+    mem->flags = kvm_mem_flags(mr);
+
+    err = kvm_set_user_memory_region(kml, mem);
+    if (err) {
+        fprintf(stderr, "%s: error registering slot: %s\n", __func__,
+                strerror(-err));
+        abort();
+    }
+}
+
+static void kvm_region_add(MemoryListener *listener,
+                           MemoryRegionSection *section)
+{
+    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
+
+    memory_region_ref(section->mr);
+    kvm_set_phys_mem(kml, section, true);
+}
+
+static void kvm_region_del(MemoryListener *listener,
+                           MemoryRegionSection *section)
+{
+    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
+
+    kvm_set_phys_mem(kml, section, false);
+    memory_region_unref(section->mr);
+}
+
+static void kvm_log_sync(MemoryListener *listener,
+                         MemoryRegionSection *section)
+{
+    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
+    int r;
+
+    r = kvm_physical_sync_dirty_bitmap(kml, section);
+    if (r < 0) {
+        abort();
+    }
+}
+
+static void kvm_mem_ioeventfd_add(MemoryListener *listener,
+                                  MemoryRegionSection *section,
+                                  bool match_data, uint64_t data,
+                                  EventNotifier *e)
+{
+    int fd = event_notifier_get_fd(e);
+    int r;
+
+    r = kvm_set_ioeventfd_mmio(fd, section->offset_within_address_space,
+                               data, true, int128_get64(section->size),
+                               match_data);
+    if (r < 0) {
+        fprintf(stderr, "%s: error adding ioeventfd: %s\n",
+                __func__, strerror(-r));
+        abort();
+    }
+}
+
+static void kvm_mem_ioeventfd_del(MemoryListener *listener,
+                                  MemoryRegionSection *section,
+                                  bool match_data, uint64_t data,
+                                  EventNotifier *e)
+{
+    int fd = event_notifier_get_fd(e);
+    int r;
+
+    r = kvm_set_ioeventfd_mmio(fd, section->offset_within_address_space,
+                               data, false, int128_get64(section->size),
+                               match_data);
+    if (r < 0) {
+        abort();
+    }
+}
+
+static void kvm_io_ioeventfd_add(MemoryListener *listener,
+                                 MemoryRegionSection *section,
+                                 bool match_data, uint64_t data,
+                                 EventNotifier *e)
+{
+    int fd = event_notifier_get_fd(e);
+    int r;
+
+    r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space,
+                              data, true, int128_get64(section->size),
+                              match_data);
+    if (r < 0) {
+        fprintf(stderr, "%s: error adding ioeventfd: %s\n",
+                __func__, strerror(-r));
+        abort();
+    }
+}
+
+static void kvm_io_ioeventfd_del(MemoryListener *listener,
+                                 MemoryRegionSection *section,
+                                 bool match_data, uint64_t data,
+                                 EventNotifier *e)
+
+{
+    int fd = event_notifier_get_fd(e);
+    int r;
+
+    r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space,
+                              data, false, int128_get64(section->size),
+                              match_data);
+    if (r < 0) {
+        abort();
+    }
+}
+
+void kvm_memory_listener_register(KVMState *s, KVMMemoryListener *kml,
+                                  AddressSpace *as, int as_id)
+{
+    int i;
+
+    kml->slots = g_malloc0(s->nr_slots * sizeof(KVMSlot));
+    kml->as_id = as_id;
+
+    for (i = 0; i < s->nr_slots; i++) {
+        kml->slots[i].slot = i;
+    }
+
+    kml->listener.region_add = kvm_region_add;
+    kml->listener.region_del = kvm_region_del;
+    kml->listener.log_start = kvm_log_start;
+    kml->listener.log_stop = kvm_log_stop;
+    kml->listener.log_sync = kvm_log_sync;
+    kml->listener.priority = 10;
+
+    memory_listener_register(&kml->listener, as);
+}
+
+static MemoryListener kvm_io_listener = {
+    .eventfd_add = kvm_io_ioeventfd_add,
+    .eventfd_del = kvm_io_ioeventfd_del,
+    .priority = 10,
+};
+
+static void kvm_handle_interrupt(CPUState *cpu, int mask)
+{
+    cpu->interrupt_request |= mask;
+
+    if (!qemu_cpu_is_self(cpu)) {
+        qemu_cpu_kick(cpu);
+    }
+}
+
+int kvm_set_irq(KVMState *s, int irq, int level)
+{
+    struct kvm_irq_level event;
+    int ret;
+
+    assert(kvm_async_interrupts_enabled());
+
+    event.level = level;
+    event.irq = irq;
+    ret = kvm_vm_ioctl(s, s->irq_set_ioctl, &event);
+    if (ret < 0) {
+        perror("kvm_set_irq");
+        abort();
+    }
+
+    return (s->irq_set_ioctl == KVM_IRQ_LINE) ? 1 : event.status;
+}
+
+#ifdef KVM_CAP_IRQ_ROUTING
+typedef struct KVMMSIRoute {
+    struct kvm_irq_routing_entry kroute;
+    QTAILQ_ENTRY(KVMMSIRoute) entry;
+} KVMMSIRoute;
+
+static void set_gsi(KVMState *s, unsigned int gsi)
+{
+    set_bit(gsi, s->used_gsi_bitmap);
+}
+
+static void clear_gsi(KVMState *s, unsigned int gsi)
+{
+    clear_bit(gsi, s->used_gsi_bitmap);
+}
+
+void kvm_init_irq_routing(KVMState *s)
+{
+    int gsi_count, i;
+
+    gsi_count = kvm_check_extension(s, KVM_CAP_IRQ_ROUTING) - 1;
+    if (gsi_count > 0) {
+        /* Round up so we can search ints using ffs */
+        s->used_gsi_bitmap = bitmap_new(gsi_count);
+        s->gsi_count = gsi_count;
+    }
+
+    s->irq_routes = g_malloc0(sizeof(*s->irq_routes));
+    s->nr_allocated_irq_routes = 0;
+
+    if (!kvm_direct_msi_allowed) {
+        for (i = 0; i < KVM_MSI_HASHTAB_SIZE; i++) {
+            QTAILQ_INIT(&s->msi_hashtab[i]);
+        }
+    }
+
+    kvm_arch_init_irq_routing(s);
+}
+
+void kvm_irqchip_commit_routes(KVMState *s)
+{
+    int ret;
+
+    if (kvm_gsi_direct_mapping()) {
+        return;
+    }
+
+    if (!kvm_gsi_routing_enabled()) {
+        return;
+    }
+
+    s->irq_routes->flags = 0;
+    trace_kvm_irqchip_commit_routes();
+    ret = kvm_vm_ioctl(s, KVM_SET_GSI_ROUTING, s->irq_routes);
+    assert(ret == 0);
+}
+
+static void kvm_add_routing_entry(KVMState *s,
+                                  struct kvm_irq_routing_entry *entry)
+{
+    struct kvm_irq_routing_entry *new;
+    int n, size;
+
+    if (s->irq_routes->nr == s->nr_allocated_irq_routes) {
+        n = s->nr_allocated_irq_routes * 2;
+        if (n < 64) {
+            n = 64;
+        }
+        size = sizeof(struct kvm_irq_routing);
+        size += n * sizeof(*new);
+        s->irq_routes = g_realloc(s->irq_routes, size);
+        s->nr_allocated_irq_routes = n;
+    }
+    n = s->irq_routes->nr++;
+    new = &s->irq_routes->entries[n];
+
+    *new = *entry;
+
+    set_gsi(s, entry->gsi);
+}
+
+static int kvm_update_routing_entry(KVMState *s,
+                                    struct kvm_irq_routing_entry *new_entry)
+{
+    struct kvm_irq_routing_entry *entry;
+    int n;
+
+    for (n = 0; n < s->irq_routes->nr; n++) {
+        entry = &s->irq_routes->entries[n];
+        if (entry->gsi != new_entry->gsi) {
+            continue;
+        }
+
+        if(!memcmp(entry, new_entry, sizeof *entry)) {
+            return 0;
+        }
+
+        *entry = *new_entry;
+
+        return 0;
+    }
+
+    return -ESRCH;
+}
+
+void kvm_irqchip_add_irq_route(KVMState *s, int irq, int irqchip, int pin)
+{
+    struct kvm_irq_routing_entry e = {};
+
+    assert(pin < s->gsi_count);
+
+    e.gsi = irq;
+    e.type = KVM_IRQ_ROUTING_IRQCHIP;
+    e.flags = 0;
+    e.u.irqchip.irqchip = irqchip;
+    e.u.irqchip.pin = pin;
+    kvm_add_routing_entry(s, &e);
+}
+
+void kvm_irqchip_release_virq(KVMState *s, int virq)
+{
+    struct kvm_irq_routing_entry *e;
+    int i;
+
+    if (kvm_gsi_direct_mapping()) {
+        return;
+    }
+
+    for (i = 0; i < s->irq_routes->nr; i++) {
+        e = &s->irq_routes->entries[i];
+        if (e->gsi == virq) {
+            s->irq_routes->nr--;
+            *e = s->irq_routes->entries[s->irq_routes->nr];
+        }
+    }
+    clear_gsi(s, virq);
+    kvm_arch_release_virq_post(virq);
+    trace_kvm_irqchip_release_virq(virq);
+}
+
+static unsigned int kvm_hash_msi(uint32_t data)
+{
+    /* This is optimized for IA32 MSI layout. However, no other arch shall
+     * repeat the mistake of not providing a direct MSI injection API. */
+    return data & 0xff;
+}
+
+static void kvm_flush_dynamic_msi_routes(KVMState *s)
+{
+    KVMMSIRoute *route, *next;
+    unsigned int hash;
+
+    for (hash = 0; hash < KVM_MSI_HASHTAB_SIZE; hash++) {
+        QTAILQ_FOREACH_SAFE(route, &s->msi_hashtab[hash], entry, next) {
+            kvm_irqchip_release_virq(s, route->kroute.gsi);
+            QTAILQ_REMOVE(&s->msi_hashtab[hash], route, entry);
+            g_free(route);
+        }
+    }
+}
+
+static int kvm_irqchip_get_virq(KVMState *s)
+{
+    int next_virq;
+
+    /*
+     * PIC and IOAPIC share the first 16 GSI numbers, thus the available
+     * GSI numbers are more than the number of IRQ route. Allocating a GSI
+     * number can succeed even though a new route entry cannot be added.
+     * When this happens, flush dynamic MSI entries to free IRQ route entries.
+     */
+    if (!kvm_direct_msi_allowed && s->irq_routes->nr == s->gsi_count) {
+        kvm_flush_dynamic_msi_routes(s);
+    }
+
+    /* Return the lowest unused GSI in the bitmap */
+    next_virq = find_first_zero_bit(s->used_gsi_bitmap, s->gsi_count);
+    if (next_virq >= s->gsi_count) {
+        return -ENOSPC;
+    } else {
+        return next_virq;
+    }
+}
+
+static KVMMSIRoute *kvm_lookup_msi_route(KVMState *s, MSIMessage msg)
+{
+    unsigned int hash = kvm_hash_msi(msg.data);
+    KVMMSIRoute *route;
+
+    QTAILQ_FOREACH(route, &s->msi_hashtab[hash], entry) {
+        if (route->kroute.u.msi.address_lo == (uint32_t)msg.address &&
+            route->kroute.u.msi.address_hi == (msg.address >> 32) &&
+            route->kroute.u.msi.data == le32_to_cpu(msg.data)) {
+            return route;
+        }
+    }
+    return NULL;
+}
+
+int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
+{
+    struct kvm_msi msi;
+    KVMMSIRoute *route;
+
+    if (kvm_direct_msi_allowed) {
+        msi.address_lo = (uint32_t)msg.address;
+        msi.address_hi = msg.address >> 32;
+        msi.data = le32_to_cpu(msg.data);
+        msi.flags = 0;
+        memset(msi.pad, 0, sizeof(msi.pad));
+
+        return kvm_vm_ioctl(s, KVM_SIGNAL_MSI, &msi);
+    }
+
+    route = kvm_lookup_msi_route(s, msg);
+    if (!route) {
+        int virq;
+
+        virq = kvm_irqchip_get_virq(s);
+        if (virq < 0) {
+            return virq;
+        }
+
+        route = g_malloc0(sizeof(KVMMSIRoute));
+        route->kroute.gsi = virq;
+        route->kroute.type = KVM_IRQ_ROUTING_MSI;
+        route->kroute.flags = 0;
+        route->kroute.u.msi.address_lo = (uint32_t)msg.address;
+        route->kroute.u.msi.address_hi = msg.address >> 32;
+        route->kroute.u.msi.data = le32_to_cpu(msg.data);
+
+        kvm_add_routing_entry(s, &route->kroute);
+        kvm_irqchip_commit_routes(s);
+
+        QTAILQ_INSERT_TAIL(&s->msi_hashtab[kvm_hash_msi(msg.data)], route,
+                           entry);
+    }
+
+    assert(route->kroute.type == KVM_IRQ_ROUTING_MSI);
+
+    return kvm_set_irq(s, route->kroute.gsi, 1);
+}
+
+int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev)
+{
+    struct kvm_irq_routing_entry kroute = {};
+    int virq;
+    MSIMessage msg = {0, 0};
+
+    if (dev) {
+        msg = pci_get_msi_message(dev, vector);
+    }
+
+    if (kvm_gsi_direct_mapping()) {
+        return kvm_arch_msi_data_to_gsi(msg.data);
+    }
+
+    if (!kvm_gsi_routing_enabled()) {
+        return -ENOSYS;
+    }
+
+    virq = kvm_irqchip_get_virq(s);
+    if (virq < 0) {
+        return virq;
+    }
+
+    kroute.gsi = virq;
+    kroute.type = KVM_IRQ_ROUTING_MSI;
+    kroute.flags = 0;
+    kroute.u.msi.address_lo = (uint32_t)msg.address;
+    kroute.u.msi.address_hi = msg.address >> 32;
+    kroute.u.msi.data = le32_to_cpu(msg.data);
+    if (kvm_msi_devid_required()) {
+        kroute.flags = KVM_MSI_VALID_DEVID;
+        kroute.u.msi.devid = pci_requester_id(dev);
+    }
+    if (kvm_arch_fixup_msi_route(&kroute, msg.address, msg.data, dev)) {
+        kvm_irqchip_release_virq(s, virq);
+        return -EINVAL;
+    }
+
+    trace_kvm_irqchip_add_msi_route(dev ? dev->name : (char *)"N/A",
+                                    vector, virq);
+
+    kvm_add_routing_entry(s, &kroute);
+    kvm_arch_add_msi_route_post(&kroute, vector, dev);
+    kvm_irqchip_commit_routes(s);
+
+    return virq;
+}
+
+int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
+                                 PCIDevice *dev)
+{
+    struct kvm_irq_routing_entry kroute = {};
+
+    if (kvm_gsi_direct_mapping()) {
+        return 0;
+    }
+
+    if (!kvm_irqchip_in_kernel()) {
+        return -ENOSYS;
+    }
+
+    kroute.gsi = virq;
+    kroute.type = KVM_IRQ_ROUTING_MSI;
+    kroute.flags = 0;
+    kroute.u.msi.address_lo = (uint32_t)msg.address;
+    kroute.u.msi.address_hi = msg.address >> 32;
+    kroute.u.msi.data = le32_to_cpu(msg.data);
+    if (kvm_msi_devid_required()) {
+        kroute.flags = KVM_MSI_VALID_DEVID;
+        kroute.u.msi.devid = pci_requester_id(dev);
+    }
+    if (kvm_arch_fixup_msi_route(&kroute, msg.address, msg.data, dev)) {
+        return -EINVAL;
+    }
+
+    trace_kvm_irqchip_update_msi_route(virq);
+
+    return kvm_update_routing_entry(s, &kroute);
+}
+
+static int kvm_irqchip_assign_irqfd(KVMState *s, int fd, int rfd, int virq,
+                                    bool assign)
+{
+    struct kvm_irqfd irqfd = {
+        .fd = fd,
+        .gsi = virq,
+        .flags = assign ? 0 : KVM_IRQFD_FLAG_DEASSIGN,
+    };
+
+    if (rfd != -1) {
+        irqfd.flags |= KVM_IRQFD_FLAG_RESAMPLE;
+        irqfd.resamplefd = rfd;
+    }
+
+    if (!kvm_irqfds_enabled()) {
+        return -ENOSYS;
+    }
+
+    return kvm_vm_ioctl(s, KVM_IRQFD, &irqfd);
+}
+
+int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
+{
+    struct kvm_irq_routing_entry kroute = {};
+    int virq;
+
+    if (!kvm_gsi_routing_enabled()) {
+        return -ENOSYS;
+    }
+
+    virq = kvm_irqchip_get_virq(s);
+    if (virq < 0) {
+        return virq;
+    }
+
+    kroute.gsi = virq;
+    kroute.type = KVM_IRQ_ROUTING_S390_ADAPTER;
+    kroute.flags = 0;
+    kroute.u.adapter.summary_addr = adapter->summary_addr;
+    kroute.u.adapter.ind_addr = adapter->ind_addr;
+    kroute.u.adapter.summary_offset = adapter->summary_offset;
+    kroute.u.adapter.ind_offset = adapter->ind_offset;
+    kroute.u.adapter.adapter_id = adapter->adapter_id;
+
+    kvm_add_routing_entry(s, &kroute);
+
+    return virq;
+}
+
+int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint)
+{
+    struct kvm_irq_routing_entry kroute = {};
+    int virq;
+
+    if (!kvm_gsi_routing_enabled()) {
+        return -ENOSYS;
+    }
+    if (!kvm_check_extension(s, KVM_CAP_HYPERV_SYNIC)) {
+        return -ENOSYS;
+    }
+    virq = kvm_irqchip_get_virq(s);
+    if (virq < 0) {
+        return virq;
+    }
+
+    kroute.gsi = virq;
+    kroute.type = KVM_IRQ_ROUTING_HV_SINT;
+    kroute.flags = 0;
+    kroute.u.hv_sint.vcpu = vcpu;
+    kroute.u.hv_sint.sint = sint;
+
+    kvm_add_routing_entry(s, &kroute);
+    kvm_irqchip_commit_routes(s);
+
+    return virq;
+}
+
+#else /* !KVM_CAP_IRQ_ROUTING */
+
+void kvm_init_irq_routing(KVMState *s)
+{
+}
+
+void kvm_irqchip_release_virq(KVMState *s, int virq)
+{
+}
+
+int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
+{
+    abort();
+}
+
+int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev)
+{
+    return -ENOSYS;
+}
+
+int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
+{
+    return -ENOSYS;
+}
+
+int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint)
+{
+    return -ENOSYS;
+}
+
+static int kvm_irqchip_assign_irqfd(KVMState *s, int fd, int virq, bool assign)
+{
+    abort();
+}
+
+int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg)
+{
+    return -ENOSYS;
+}
+#endif /* !KVM_CAP_IRQ_ROUTING */
+
+int kvm_irqchip_add_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
+                                       EventNotifier *rn, int virq)
+{
+    return kvm_irqchip_assign_irqfd(s, event_notifier_get_fd(n),
+           rn ? event_notifier_get_fd(rn) : -1, virq, true);
+}
+
+int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
+                                          int virq)
+{
+    return kvm_irqchip_assign_irqfd(s, event_notifier_get_fd(n), -1, virq,
+           false);
+}
+
+int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
+                                   EventNotifier *rn, qemu_irq irq)
+{
+    gpointer key, gsi;
+    gboolean found = g_hash_table_lookup_extended(s->gsimap, irq, &key, &gsi);
+
+    if (!found) {
+        return -ENXIO;
+    }
+    return kvm_irqchip_add_irqfd_notifier_gsi(s, n, rn, GPOINTER_TO_INT(gsi));
+}
+
+int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n,
+                                      qemu_irq irq)
+{
+    gpointer key, gsi;
+    gboolean found = g_hash_table_lookup_extended(s->gsimap, irq, &key, &gsi);
+
+    if (!found) {
+        return -ENXIO;
+    }
+    return kvm_irqchip_remove_irqfd_notifier_gsi(s, n, GPOINTER_TO_INT(gsi));
+}
+
+void kvm_irqchip_set_qemuirq_gsi(KVMState *s, qemu_irq irq, int gsi)
+{
+    g_hash_table_insert(s->gsimap, irq, GINT_TO_POINTER(gsi));
+}
+
+static void kvm_irqchip_create(MachineState *machine, KVMState *s)
+{
+    int ret;
+
+    if (kvm_check_extension(s, KVM_CAP_IRQCHIP)) {
+        ;
+    } else if (kvm_check_extension(s, KVM_CAP_S390_IRQCHIP)) {
+        ret = kvm_vm_enable_cap(s, KVM_CAP_S390_IRQCHIP, 0);
+        if (ret < 0) {
+            fprintf(stderr, "Enable kernel irqchip failed: %s\n", strerror(-ret));
+            exit(1);
+        }
+    } else {
+        return;
+    }
+
+    /* First probe and see if there's a arch-specific hook to create the
+     * in-kernel irqchip for us */
+    ret = kvm_arch_irqchip_create(machine, s);
+    if (ret == 0) {
+        if (machine_kernel_irqchip_split(machine)) {
+            perror("Split IRQ chip mode not supported.");
+            exit(1);
+        } else {
+            ret = kvm_vm_ioctl(s, KVM_CREATE_IRQCHIP);
+        }
+    }
+    if (ret < 0) {
+        fprintf(stderr, "Create kernel irqchip failed: %s\n", strerror(-ret));
+        exit(1);
+    }
+
+    kvm_kernel_irqchip = true;
+    /* If we have an in-kernel IRQ chip then we must have asynchronous
+     * interrupt delivery (though the reverse is not necessarily true)
+     */
+    kvm_async_interrupts_allowed = true;
+    kvm_halt_in_kernel_allowed = true;
+
+    kvm_init_irq_routing(s);
+
+    s->gsimap = g_hash_table_new(g_direct_hash, g_direct_equal);
+}
+
+/* Find number of supported CPUs using the recommended
+ * procedure from the kernel API documentation to cope with
+ * older kernels that may be missing capabilities.
+ */
+static int kvm_recommended_vcpus(KVMState *s)
+{
+    int ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS);
+    return (ret) ? ret : 4;
+}
+
+static int kvm_max_vcpus(KVMState *s)
+{
+    int ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
+    return (ret) ? ret : kvm_recommended_vcpus(s);
+}
+
+static int kvm_max_vcpu_id(KVMState *s)
+{
+    int ret = kvm_check_extension(s, KVM_CAP_MAX_VCPU_ID);
+    return (ret) ? ret : kvm_max_vcpus(s);
+}
+
+bool kvm_vcpu_id_is_valid(int vcpu_id)
+{
+    KVMState *s = KVM_STATE(current_machine->accelerator);
+    return vcpu_id >= 0 && vcpu_id < kvm_max_vcpu_id(s);
+}
+
+static int kvm_init(MachineState *ms)
+{
+    MachineClass *mc = MACHINE_GET_CLASS(ms);
+    static const char upgrade_note[] =
+        "Please upgrade to at least kernel 2.6.29 or recent kvm-kmod\n"
+        "(see http://sourceforge.net/projects/kvm).\n";
+    struct {
+        const char *name;
+        int num;
+    } num_cpus[] = {
+        { "SMP",          smp_cpus },
+        { "hotpluggable", max_cpus },
+        { NULL, }
+    }, *nc = num_cpus;
+    int soft_vcpus_limit, hard_vcpus_limit;
+    KVMState *s;
+    const KVMCapabilityInfo *missing_cap;
+    int ret;
+    int type = 0;
+    const char *kvm_type;
+
+    s = KVM_STATE(ms->accelerator);
+
+    /*
+     * On systems where the kernel can support different base page
+     * sizes, host page size may be different from TARGET_PAGE_SIZE,
+     * even with KVM.  TARGET_PAGE_SIZE is assumed to be the minimum
+     * page size for the system though.
+     */
+    assert(TARGET_PAGE_SIZE <= getpagesize());
+
+    s->sigmask_len = 8;
+
+#ifdef KVM_CAP_SET_GUEST_DEBUG
+    QTAILQ_INIT(&s->kvm_sw_breakpoints);
+#endif
+    QLIST_INIT(&s->kvm_parked_vcpus);
+    s->vmfd = -1;
+    s->fd = qemu_open("/dev/kvm", O_RDWR);
+    if (s->fd == -1) {
+        fprintf(stderr, "Could not access KVM kernel module: %m\n");
+        ret = -errno;
+        goto err;
+    }
+
+    ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
+    if (ret < KVM_API_VERSION) {
+        if (ret >= 0) {
+            ret = -EINVAL;
+        }
+        fprintf(stderr, "kvm version too old\n");
+        goto err;
+    }
+
+    if (ret > KVM_API_VERSION) {
+        ret = -EINVAL;
+        fprintf(stderr, "kvm version not supported\n");
+        goto err;
+    }
+
+    kvm_immediate_exit = kvm_check_extension(s, KVM_CAP_IMMEDIATE_EXIT);
+    s->nr_slots = kvm_check_extension(s, KVM_CAP_NR_MEMSLOTS);
+
+    /* If unspecified, use the default value */
+    if (!s->nr_slots) {
+        s->nr_slots = 32;
+    }
+
+    /* check the vcpu limits */
+    soft_vcpus_limit = kvm_recommended_vcpus(s);
+    hard_vcpus_limit = kvm_max_vcpus(s);
+
+    while (nc->name) {
+        if (nc->num > soft_vcpus_limit) {
+            fprintf(stderr,
+                    "Warning: Number of %s cpus requested (%d) exceeds "
+                    "the recommended cpus supported by KVM (%d)\n",
+                    nc->name, nc->num, soft_vcpus_limit);
+
+            if (nc->num > hard_vcpus_limit) {
+                fprintf(stderr, "Number of %s cpus requested (%d) exceeds "
+                        "the maximum cpus supported by KVM (%d)\n",
+                        nc->name, nc->num, hard_vcpus_limit);
+                exit(1);
+            }
+        }
+        nc++;
+    }
+
+    kvm_type = qemu_opt_get(qemu_get_machine_opts(), "kvm-type");
+    if (mc->kvm_type) {
+        type = mc->kvm_type(kvm_type);
+    } else if (kvm_type) {
+        ret = -EINVAL;
+        fprintf(stderr, "Invalid argument kvm-type=%s\n", kvm_type);
+        goto err;
+    }
+
+    do {
+        ret = kvm_ioctl(s, KVM_CREATE_VM, type);
+    } while (ret == -EINTR);
+
+    if (ret < 0) {
+        fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %d %s\n", -ret,
+                strerror(-ret));
+
+#ifdef TARGET_S390X
+        if (ret == -EINVAL) {
+            fprintf(stderr,
+                    "Host kernel setup problem detected. Please verify:\n");
+            fprintf(stderr, "- for kernels supporting the switch_amode or"
+                    " user_mode parameters, whether\n");
+            fprintf(stderr,
+                    "  user space is running in primary address space\n");
+            fprintf(stderr,
+                    "- for kernels supporting the vm.allocate_pgste sysctl, "
+                    "whether it is enabled\n");
+        }
+#endif
+        goto err;
+    }
+
+    s->vmfd = ret;
+    missing_cap = kvm_check_extension_list(s, kvm_required_capabilites);
+    if (!missing_cap) {
+        missing_cap =
+            kvm_check_extension_list(s, kvm_arch_required_capabilities);
+    }
+    if (missing_cap) {
+        ret = -EINVAL;
+        fprintf(stderr, "kvm does not support %s\n%s",
+                missing_cap->name, upgrade_note);
+        goto err;
+    }
+
+    s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
+
+    s->broken_set_mem_region = 1;
+    ret = kvm_check_extension(s, KVM_CAP_JOIN_MEMORY_REGIONS_WORKS);
+    if (ret > 0) {
+        s->broken_set_mem_region = 0;
+    }
+
+#ifdef KVM_CAP_VCPU_EVENTS
+    s->vcpu_events = kvm_check_extension(s, KVM_CAP_VCPU_EVENTS);
+#endif
+
+    s->robust_singlestep =
+        kvm_check_extension(s, KVM_CAP_X86_ROBUST_SINGLESTEP);
+
+#ifdef KVM_CAP_DEBUGREGS
+    s->debugregs = kvm_check_extension(s, KVM_CAP_DEBUGREGS);
+#endif
+
+#ifdef KVM_CAP_IRQ_ROUTING
+    kvm_direct_msi_allowed = (kvm_check_extension(s, KVM_CAP_SIGNAL_MSI) > 0);
+#endif
+
+    s->intx_set_mask = kvm_check_extension(s, KVM_CAP_PCI_2_3);
+
+    s->irq_set_ioctl = KVM_IRQ_LINE;
+    if (kvm_check_extension(s, KVM_CAP_IRQ_INJECT_STATUS)) {
+        s->irq_set_ioctl = KVM_IRQ_LINE_STATUS;
+    }
+
+#ifdef KVM_CAP_READONLY_MEM
+    kvm_readonly_mem_allowed =
+        (kvm_check_extension(s, KVM_CAP_READONLY_MEM) > 0);
+#endif
+
+    kvm_eventfds_allowed =
+        (kvm_check_extension(s, KVM_CAP_IOEVENTFD) > 0);
+
+    kvm_irqfds_allowed =
+        (kvm_check_extension(s, KVM_CAP_IRQFD) > 0);
+
+    kvm_resamplefds_allowed =
+        (kvm_check_extension(s, KVM_CAP_IRQFD_RESAMPLE) > 0);
+
+    kvm_vm_attributes_allowed =
+        (kvm_check_extension(s, KVM_CAP_VM_ATTRIBUTES) > 0);
+
+    kvm_ioeventfd_any_length_allowed =
+        (kvm_check_extension(s, KVM_CAP_IOEVENTFD_ANY_LENGTH) > 0);
+
+    kvm_state = s;
+
+    ret = kvm_arch_init(ms, s);
+    if (ret < 0) {
+        goto err;
+    }
+
+    if (machine_kernel_irqchip_allowed(ms)) {
+        kvm_irqchip_create(ms, s);
+    }
+
+    if (kvm_eventfds_allowed) {
+        s->memory_listener.listener.eventfd_add = kvm_mem_ioeventfd_add;
+        s->memory_listener.listener.eventfd_del = kvm_mem_ioeventfd_del;
+    }
+    s->memory_listener.listener.coalesced_mmio_add = kvm_coalesce_mmio_region;
+    s->memory_listener.listener.coalesced_mmio_del = kvm_uncoalesce_mmio_region;
+
+    kvm_memory_listener_register(s, &s->memory_listener,
+                                 &address_space_memory, 0);
+    memory_listener_register(&kvm_io_listener,
+                             &address_space_io);
+
+    s->many_ioeventfds = kvm_check_many_ioeventfds();
+
+    cpu_interrupt_handler = kvm_handle_interrupt;
+
+    return 0;
+
+err:
+    assert(ret < 0);
+    if (s->vmfd >= 0) {
+        close(s->vmfd);
+    }
+    if (s->fd != -1) {
+        close(s->fd);
+    }
+    g_free(s->memory_listener.slots);
+
+    return ret;
+}
+
+void kvm_set_sigmask_len(KVMState *s, unsigned int sigmask_len)
+{
+    s->sigmask_len = sigmask_len;
+}
+
+static void kvm_handle_io(uint16_t port, MemTxAttrs attrs, void *data, int direction,
+                          int size, uint32_t count)
+{
+    int i;
+    uint8_t *ptr = data;
+
+    for (i = 0; i < count; i++) {
+        address_space_rw(&address_space_io, port, attrs,
+                         ptr, size,
+                         direction == KVM_EXIT_IO_OUT);
+        ptr += size;
+    }
+}
+
+static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run)
+{
+    fprintf(stderr, "KVM internal error. Suberror: %d\n",
+            run->internal.suberror);
+
+    if (kvm_check_extension(kvm_state, KVM_CAP_INTERNAL_ERROR_DATA)) {
+        int i;
+
+        for (i = 0; i < run->internal.ndata; ++i) {
+            fprintf(stderr, "extra data[%d]: %"PRIx64"\n",
+                    i, (uint64_t)run->internal.data[i]);
+        }
+    }
+    if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) {
+        fprintf(stderr, "emulation failure\n");
+        if (!kvm_arch_stop_on_emulation_error(cpu)) {
+            cpu_dump_state(cpu, stderr, fprintf, CPU_DUMP_CODE);
+            return EXCP_INTERRUPT;
+        }
+    }
+    /* FIXME: Should trigger a qmp message to let management know
+     * something went wrong.
+     */
+    return -1;
+}
+
+void kvm_flush_coalesced_mmio_buffer(void)
+{
+    KVMState *s = kvm_state;
+
+    if (s->coalesced_flush_in_progress) {
+        return;
+    }
+
+    s->coalesced_flush_in_progress = true;
+
+    if (s->coalesced_mmio_ring) {
+        struct kvm_coalesced_mmio_ring *ring = s->coalesced_mmio_ring;
+        while (ring->first != ring->last) {
+            struct kvm_coalesced_mmio *ent;
+
+            ent = &ring->coalesced_mmio[ring->first];
+
+            cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
+            smp_wmb();
+            ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
+        }
+    }
+
+    s->coalesced_flush_in_progress = false;
+}
+
+static void do_kvm_cpu_synchronize_state(CPUState *cpu, run_on_cpu_data arg)
+{
+    if (!cpu->kvm_vcpu_dirty) {
+        kvm_arch_get_registers(cpu);
+        cpu->kvm_vcpu_dirty = true;
+    }
+}
+
+void kvm_cpu_synchronize_state(CPUState *cpu)
+{
+    if (!cpu->kvm_vcpu_dirty) {
+        run_on_cpu(cpu, do_kvm_cpu_synchronize_state, RUN_ON_CPU_NULL);
+    }
+}
+
+static void do_kvm_cpu_synchronize_post_reset(CPUState *cpu, run_on_cpu_data arg)
+{
+    kvm_arch_put_registers(cpu, KVM_PUT_RESET_STATE);
+    cpu->kvm_vcpu_dirty = false;
+}
+
+void kvm_cpu_synchronize_post_reset(CPUState *cpu)
+{
+    run_on_cpu(cpu, do_kvm_cpu_synchronize_post_reset, RUN_ON_CPU_NULL);
+}
+
+static void do_kvm_cpu_synchronize_post_init(CPUState *cpu, run_on_cpu_data arg)
+{
+    kvm_arch_put_registers(cpu, KVM_PUT_FULL_STATE);
+    cpu->kvm_vcpu_dirty = false;
+}
+
+void kvm_cpu_synchronize_post_init(CPUState *cpu)
+{
+    run_on_cpu(cpu, do_kvm_cpu_synchronize_post_init, RUN_ON_CPU_NULL);
+}
+
+static void do_kvm_cpu_synchronize_pre_loadvm(CPUState *cpu, run_on_cpu_data arg)
+{
+    cpu->kvm_vcpu_dirty = true;
+}
+
+void kvm_cpu_synchronize_pre_loadvm(CPUState *cpu)
+{
+    run_on_cpu(cpu, do_kvm_cpu_synchronize_pre_loadvm, RUN_ON_CPU_NULL);
+}
+
+#ifdef KVM_HAVE_MCE_INJECTION
+static __thread void *pending_sigbus_addr;
+static __thread int pending_sigbus_code;
+static __thread bool have_sigbus_pending;
+#endif
+
+static void kvm_cpu_kick(CPUState *cpu)
+{
+    atomic_set(&cpu->kvm_run->immediate_exit, 1);
+}
+
+static void kvm_cpu_kick_self(void)
+{
+    if (kvm_immediate_exit) {
+        kvm_cpu_kick(current_cpu);
+    } else {
+        qemu_cpu_kick_self();
+    }
+}
+
+static void kvm_eat_signals(CPUState *cpu)
+{
+    struct timespec ts = { 0, 0 };
+    siginfo_t siginfo;
+    sigset_t waitset;
+    sigset_t chkset;
+    int r;
+
+    if (kvm_immediate_exit) {
+        atomic_set(&cpu->kvm_run->immediate_exit, 0);
+        /* Write kvm_run->immediate_exit before the cpu->exit_request
+         * write in kvm_cpu_exec.
+         */
+        smp_wmb();
+        return;
+    }
+
+    sigemptyset(&waitset);
+    sigaddset(&waitset, SIG_IPI);
+
+    do {
+        r = sigtimedwait(&waitset, &siginfo, &ts);
+        if (r == -1 && !(errno == EAGAIN || errno == EINTR)) {
+            perror("sigtimedwait");
+            exit(1);
+        }
+
+        r = sigpending(&chkset);
+        if (r == -1) {
+            perror("sigpending");
+            exit(1);
+        }
+    } while (sigismember(&chkset, SIG_IPI));
+}
+
+int kvm_cpu_exec(CPUState *cpu)
+{
+    struct kvm_run *run = cpu->kvm_run;
+    int ret, run_ret;
+
+    DPRINTF("kvm_cpu_exec()\n");
+
+    if (kvm_arch_process_async_events(cpu)) {
+        atomic_set(&cpu->exit_request, 0);
+        return EXCP_HLT;
+    }
+
+    qemu_mutex_unlock_iothread();
+    cpu_exec_start(cpu);
+
+    do {
+        MemTxAttrs attrs;
+
+        if (cpu->kvm_vcpu_dirty) {
+            kvm_arch_put_registers(cpu, KVM_PUT_RUNTIME_STATE);
+            cpu->kvm_vcpu_dirty = false;
+        }
+
+        kvm_arch_pre_run(cpu, run);
+        if (atomic_read(&cpu->exit_request)) {
+            DPRINTF("interrupt exit requested\n");
+            /*
+             * KVM requires us to reenter the kernel after IO exits to complete
+             * instruction emulation. This self-signal will ensure that we
+             * leave ASAP again.
+             */
+            kvm_cpu_kick_self();
+        }
+
+        /* Read cpu->exit_request before KVM_RUN reads run->immediate_exit.
+         * Matching barrier in kvm_eat_signals.
+         */
+        smp_rmb();
+
+        run_ret = kvm_vcpu_ioctl(cpu, KVM_RUN, 0);
+
+        attrs = kvm_arch_post_run(cpu, run);
+
+#ifdef KVM_HAVE_MCE_INJECTION
+        if (unlikely(have_sigbus_pending)) {
+            qemu_mutex_lock_iothread();
+            kvm_arch_on_sigbus_vcpu(cpu, pending_sigbus_code,
+                                    pending_sigbus_addr);
+            have_sigbus_pending = false;
+            qemu_mutex_unlock_iothread();
+        }
+#endif
+
+        if (run_ret < 0) {
+            if (run_ret == -EINTR || run_ret == -EAGAIN) {
+                DPRINTF("io window exit\n");
+                kvm_eat_signals(cpu);
+                ret = EXCP_INTERRUPT;
+                break;
+            }
+            fprintf(stderr, "error: kvm run failed %s\n",
+                    strerror(-run_ret));
+#ifdef TARGET_PPC
+            if (run_ret == -EBUSY) {
+                fprintf(stderr,
+                        "This is probably because your SMT is enabled.\n"
+                        "VCPU can only run on primary threads with all "
+                        "secondary threads offline.\n");
+            }
+#endif
+            ret = -1;
+            break;
+        }
+
+        trace_kvm_run_exit(cpu->cpu_index, run->exit_reason);
+        switch (run->exit_reason) {
+        case KVM_EXIT_IO:
+            DPRINTF("handle_io\n");
+            /* Called outside BQL */
+            kvm_handle_io(run->io.port, attrs,
+                          (uint8_t *)run + run->io.data_offset,
+                          run->io.direction,
+                          run->io.size,
+                          run->io.count);
+            ret = 0;
+            break;
+        case KVM_EXIT_MMIO:
+            DPRINTF("handle_mmio\n");
+            /* Called outside BQL */
+            address_space_rw(&address_space_memory,
+                             run->mmio.phys_addr, attrs,
+                             run->mmio.data,
+                             run->mmio.len,
+                             run->mmio.is_write);
+            ret = 0;
+            break;
+        case KVM_EXIT_IRQ_WINDOW_OPEN:
+            DPRINTF("irq_window_open\n");
+            ret = EXCP_INTERRUPT;
+            break;
+        case KVM_EXIT_SHUTDOWN:
+            DPRINTF("shutdown\n");
+            qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
+            ret = EXCP_INTERRUPT;
+            break;
+        case KVM_EXIT_UNKNOWN:
+            fprintf(stderr, "KVM: unknown exit, hardware reason %" PRIx64 "\n",
+                    (uint64_t)run->hw.hardware_exit_reason);
+            ret = -1;
+            break;
+        case KVM_EXIT_INTERNAL_ERROR:
+            ret = kvm_handle_internal_error(cpu, run);
+            break;
+        case KVM_EXIT_SYSTEM_EVENT:
+            switch (run->system_event.type) {
+            case KVM_SYSTEM_EVENT_SHUTDOWN:
+                qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
+                ret = EXCP_INTERRUPT;
+                break;
+            case KVM_SYSTEM_EVENT_RESET:
+                qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
+                ret = EXCP_INTERRUPT;
+                break;
+            case KVM_SYSTEM_EVENT_CRASH:
+                kvm_cpu_synchronize_state(cpu);
+                qemu_mutex_lock_iothread();
+                qemu_system_guest_panicked(cpu_get_crash_info(cpu));
+                qemu_mutex_unlock_iothread();
+                ret = 0;
+                break;
+            default:
+                DPRINTF("kvm_arch_handle_exit\n");
+                ret = kvm_arch_handle_exit(cpu, run);
+                break;
+            }
+            break;
+        default:
+            DPRINTF("kvm_arch_handle_exit\n");
+            ret = kvm_arch_handle_exit(cpu, run);
+            break;
+        }
+    } while (ret == 0);
+
+    cpu_exec_end(cpu);
+    qemu_mutex_lock_iothread();
+
+    if (ret < 0) {
+        cpu_dump_state(cpu, stderr, fprintf, CPU_DUMP_CODE);
+        vm_stop(RUN_STATE_INTERNAL_ERROR);
+    }
+
+    atomic_set(&cpu->exit_request, 0);
+    return ret;
+}
+
+int kvm_ioctl(KVMState *s, int type, ...)
+{
+    int ret;
+    void *arg;
+    va_list ap;
+
+    va_start(ap, type);
+    arg = va_arg(ap, void *);
+    va_end(ap);
+
+    trace_kvm_ioctl(type, arg);
+    ret = ioctl(s->fd, type, arg);
+    if (ret == -1) {
+        ret = -errno;
+    }
+    return ret;
+}
+
+int kvm_vm_ioctl(KVMState *s, int type, ...)
+{
+    int ret;
+    void *arg;
+    va_list ap;
+
+    va_start(ap, type);
+    arg = va_arg(ap, void *);
+    va_end(ap);
+
+    trace_kvm_vm_ioctl(type, arg);
+    ret = ioctl(s->vmfd, type, arg);
+    if (ret == -1) {
+        ret = -errno;
+    }
+    return ret;
+}
+
+int kvm_vcpu_ioctl(CPUState *cpu, int type, ...)
+{
+    int ret;
+    void *arg;
+    va_list ap;
+
+    va_start(ap, type);
+    arg = va_arg(ap, void *);
+    va_end(ap);
+
+    trace_kvm_vcpu_ioctl(cpu->cpu_index, type, arg);
+    ret = ioctl(cpu->kvm_fd, type, arg);
+    if (ret == -1) {
+        ret = -errno;
+    }
+    return ret;
+}
+
+int kvm_device_ioctl(int fd, int type, ...)
+{
+    int ret;
+    void *arg;
+    va_list ap;
+
+    va_start(ap, type);
+    arg = va_arg(ap, void *);
+    va_end(ap);
+
+    trace_kvm_device_ioctl(fd, type, arg);
+    ret = ioctl(fd, type, arg);
+    if (ret == -1) {
+        ret = -errno;
+    }
+    return ret;
+}
+
+int kvm_vm_check_attr(KVMState *s, uint32_t group, uint64_t attr)
+{
+    int ret;
+    struct kvm_device_attr attribute = {
+        .group = group,
+        .attr = attr,
+    };
+
+    if (!kvm_vm_attributes_allowed) {
+        return 0;
+    }
+
+    ret = kvm_vm_ioctl(s, KVM_HAS_DEVICE_ATTR, &attribute);
+    /* kvm returns 0 on success for HAS_DEVICE_ATTR */
+    return ret ? 0 : 1;
+}
+
+int kvm_device_check_attr(int dev_fd, uint32_t group, uint64_t attr)
+{
+    struct kvm_device_attr attribute = {
+        .group = group,
+        .attr = attr,
+        .flags = 0,
+    };
+
+    return kvm_device_ioctl(dev_fd, KVM_HAS_DEVICE_ATTR, &attribute) ? 0 : 1;
+}
+
+int kvm_device_access(int fd, int group, uint64_t attr,
+                      void *val, bool write, Error **errp)
+{
+    struct kvm_device_attr kvmattr;
+    int err;
+
+    kvmattr.flags = 0;
+    kvmattr.group = group;
+    kvmattr.attr = attr;
+    kvmattr.addr = (uintptr_t)val;
+
+    err = kvm_device_ioctl(fd,
+                           write ? KVM_SET_DEVICE_ATTR : KVM_GET_DEVICE_ATTR,
+                           &kvmattr);
+    if (err < 0) {
+        error_setg_errno(errp, -err,
+                         "KVM_%s_DEVICE_ATTR failed: Group %d "
+                         "attr 0x%016" PRIx64,
+                         write ? "SET" : "GET", group, attr);
+    }
+    return err;
+}
+
+/* Return 1 on success, 0 on failure */
+int kvm_has_sync_mmu(void)
+{
+    return kvm_check_extension(kvm_state, KVM_CAP_SYNC_MMU);
+}
+
+int kvm_has_vcpu_events(void)
+{
+    return kvm_state->vcpu_events;
+}
+
+int kvm_has_robust_singlestep(void)
+{
+    return kvm_state->robust_singlestep;
+}
+
+int kvm_has_debugregs(void)
+{
+    return kvm_state->debugregs;
+}
+
+int kvm_has_many_ioeventfds(void)
+{
+    if (!kvm_enabled()) {
+        return 0;
+    }
+    return kvm_state->many_ioeventfds;
+}
+
+int kvm_has_gsi_routing(void)
+{
+#ifdef KVM_CAP_IRQ_ROUTING
+    return kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING);
+#else
+    return false;
+#endif
+}
+
+int kvm_has_intx_set_mask(void)
+{
+    return kvm_state->intx_set_mask;
+}
+
+#ifdef KVM_CAP_SET_GUEST_DEBUG
+struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *cpu,
+                                                 target_ulong pc)
+{
+    struct kvm_sw_breakpoint *bp;
+
+    QTAILQ_FOREACH(bp, &cpu->kvm_state->kvm_sw_breakpoints, entry) {
+        if (bp->pc == pc) {
+            return bp;
+        }
+    }
+    return NULL;
+}
+
+int kvm_sw_breakpoints_active(CPUState *cpu)
+{
+    return !QTAILQ_EMPTY(&cpu->kvm_state->kvm_sw_breakpoints);
+}
+
+struct kvm_set_guest_debug_data {
+    struct kvm_guest_debug dbg;
+    int err;
+};
+
+static void kvm_invoke_set_guest_debug(CPUState *cpu, run_on_cpu_data data)
+{
+    struct kvm_set_guest_debug_data *dbg_data =
+        (struct kvm_set_guest_debug_data *) data.host_ptr;
+
+    dbg_data->err = kvm_vcpu_ioctl(cpu, KVM_SET_GUEST_DEBUG,
+                                   &dbg_data->dbg);
+}
+
+int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
+{
+    struct kvm_set_guest_debug_data data;
+
+    data.dbg.control = reinject_trap;
+
+    if (cpu->singlestep_enabled) {
+        data.dbg.control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
+    }
+    kvm_arch_update_guest_debug(cpu, &data.dbg);
+
+    run_on_cpu(cpu, kvm_invoke_set_guest_debug,
+               RUN_ON_CPU_HOST_PTR(&data));
+    return data.err;
+}
+
+int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
+                          target_ulong len, int type)
+{
+    struct kvm_sw_breakpoint *bp;
+    int err;
+
+    if (type == GDB_BREAKPOINT_SW) {
+        bp = kvm_find_sw_breakpoint(cpu, addr);
+        if (bp) {
+            bp->use_count++;
+            return 0;
+        }
+
+        bp = g_malloc(sizeof(struct kvm_sw_breakpoint));
+        bp->pc = addr;
+        bp->use_count = 1;
+        err = kvm_arch_insert_sw_breakpoint(cpu, bp);
+        if (err) {
+            g_free(bp);
+            return err;
+        }
+
+        QTAILQ_INSERT_HEAD(&cpu->kvm_state->kvm_sw_breakpoints, bp, entry);
+    } else {
+        err = kvm_arch_insert_hw_breakpoint(addr, len, type);
+        if (err) {
+            return err;
+        }
+    }
+
+    CPU_FOREACH(cpu) {
+        err = kvm_update_guest_debug(cpu, 0);
+        if (err) {
+            return err;
+        }
+    }
+    return 0;
+}
+
+int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
+                          target_ulong len, int type)
+{
+    struct kvm_sw_breakpoint *bp;
+    int err;
+
+    if (type == GDB_BREAKPOINT_SW) {
+        bp = kvm_find_sw_breakpoint(cpu, addr);
+        if (!bp) {
+            return -ENOENT;
+        }
+
+        if (bp->use_count > 1) {
+            bp->use_count--;
+            return 0;
+        }
+
+        err = kvm_arch_remove_sw_breakpoint(cpu, bp);
+        if (err) {
+            return err;
+        }
+
+        QTAILQ_REMOVE(&cpu->kvm_state->kvm_sw_breakpoints, bp, entry);
+        g_free(bp);
+    } else {
+        err = kvm_arch_remove_hw_breakpoint(addr, len, type);
+        if (err) {
+            return err;
+        }
+    }
+
+    CPU_FOREACH(cpu) {
+        err = kvm_update_guest_debug(cpu, 0);
+        if (err) {
+            return err;
+        }
+    }
+    return 0;
+}
+
+void kvm_remove_all_breakpoints(CPUState *cpu)
+{
+    struct kvm_sw_breakpoint *bp, *next;
+    KVMState *s = cpu->kvm_state;
+    CPUState *tmpcpu;
+
+    QTAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) {
+        if (kvm_arch_remove_sw_breakpoint(cpu, bp) != 0) {
+            /* Try harder to find a CPU that currently sees the breakpoint. */
+            CPU_FOREACH(tmpcpu) {
+                if (kvm_arch_remove_sw_breakpoint(tmpcpu, bp) == 0) {
+                    break;
+                }
+            }
+        }
+        QTAILQ_REMOVE(&s->kvm_sw_breakpoints, bp, entry);
+        g_free(bp);
+    }
+    kvm_arch_remove_all_hw_breakpoints();
+
+    CPU_FOREACH(cpu) {
+        kvm_update_guest_debug(cpu, 0);
+    }
+}
+
+#else /* !KVM_CAP_SET_GUEST_DEBUG */
+
+int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
+{
+    return -EINVAL;
+}
+
+int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
+                          target_ulong len, int type)
+{
+    return -EINVAL;
+}
+
+int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
+                          target_ulong len, int type)
+{
+    return -EINVAL;
+}
+
+void kvm_remove_all_breakpoints(CPUState *cpu)
+{
+}
+#endif /* !KVM_CAP_SET_GUEST_DEBUG */
+
+static int kvm_set_signal_mask(CPUState *cpu, const sigset_t *sigset)
+{
+    KVMState *s = kvm_state;
+    struct kvm_signal_mask *sigmask;
+    int r;
+
+    sigmask = g_malloc(sizeof(*sigmask) + sizeof(*sigset));
+
+    sigmask->len = s->sigmask_len;
+    memcpy(sigmask->sigset, sigset, sizeof(*sigset));
+    r = kvm_vcpu_ioctl(cpu, KVM_SET_SIGNAL_MASK, sigmask);
+    g_free(sigmask);
+
+    return r;
+}
+
+static void kvm_ipi_signal(int sig)
+{
+    if (current_cpu) {
+        assert(kvm_immediate_exit);
+        kvm_cpu_kick(current_cpu);
+    }
+}
+
+void kvm_init_cpu_signals(CPUState *cpu)
+{
+    int r;
+    sigset_t set;
+    struct sigaction sigact;
+
+    memset(&sigact, 0, sizeof(sigact));
+    sigact.sa_handler = kvm_ipi_signal;
+    sigaction(SIG_IPI, &sigact, NULL);
+
+    pthread_sigmask(SIG_BLOCK, NULL, &set);
+#if defined KVM_HAVE_MCE_INJECTION
+    sigdelset(&set, SIGBUS);
+    pthread_sigmask(SIG_SETMASK, &set, NULL);
+#endif
+    sigdelset(&set, SIG_IPI);
+    if (kvm_immediate_exit) {
+        r = pthread_sigmask(SIG_SETMASK, &set, NULL);
+    } else {
+        r = kvm_set_signal_mask(cpu, &set);
+    }
+    if (r) {
+        fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));
+        exit(1);
+    }
+}
+
+/* Called asynchronously in VCPU thread.  */
+int kvm_on_sigbus_vcpu(CPUState *cpu, int code, void *addr)
+{
+#ifdef KVM_HAVE_MCE_INJECTION
+    if (have_sigbus_pending) {
+        return 1;
+    }
+    have_sigbus_pending = true;
+    pending_sigbus_addr = addr;
+    pending_sigbus_code = code;
+    atomic_set(&cpu->exit_request, 1);
+    return 0;
+#else
+    return 1;
+#endif
+}
+
+/* Called synchronously (via signalfd) in main thread.  */
+int kvm_on_sigbus(int code, void *addr)
+{
+#ifdef KVM_HAVE_MCE_INJECTION
+    /* Action required MCE kills the process if SIGBUS is blocked.  Because
+     * that's what happens in the I/O thread, where we handle MCE via signalfd,
+     * we can only get action optional here.
+     */
+    assert(code != BUS_MCEERR_AR);
+    kvm_arch_on_sigbus_vcpu(first_cpu, code, addr);
+    return 0;
+#else
+    return 1;
+#endif
+}
+
+int kvm_create_device(KVMState *s, uint64_t type, bool test)
+{
+    int ret;
+    struct kvm_create_device create_dev;
+
+    create_dev.type = type;
+    create_dev.fd = -1;
+    create_dev.flags = test ? KVM_CREATE_DEVICE_TEST : 0;
+
+    if (!kvm_check_extension(s, KVM_CAP_DEVICE_CTRL)) {
+        return -ENOTSUP;
+    }
+
+    ret = kvm_vm_ioctl(s, KVM_CREATE_DEVICE, &create_dev);
+    if (ret) {
+        return ret;
+    }
+
+    return test ? 0 : create_dev.fd;
+}
+
+bool kvm_device_supported(int vmfd, uint64_t type)
+{
+    struct kvm_create_device create_dev = {
+        .type = type,
+        .fd = -1,
+        .flags = KVM_CREATE_DEVICE_TEST,
+    };
+
+    if (ioctl(vmfd, KVM_CHECK_EXTENSION, KVM_CAP_DEVICE_CTRL) <= 0) {
+        return false;
+    }
+
+    return (ioctl(vmfd, KVM_CREATE_DEVICE, &create_dev) >= 0);
+}
+
+int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source)
+{
+    struct kvm_one_reg reg;
+    int r;
+
+    reg.id = id;
+    reg.addr = (uintptr_t) source;
+    r = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
+    if (r) {
+        trace_kvm_failed_reg_set(id, strerror(-r));
+    }
+    return r;
+}
+
+int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target)
+{
+    struct kvm_one_reg reg;
+    int r;
+
+    reg.id = id;
+    reg.addr = (uintptr_t) target;
+    r = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
+    if (r) {
+        trace_kvm_failed_reg_get(id, strerror(-r));
+    }
+    return r;
+}
+
+static void kvm_accel_class_init(ObjectClass *oc, void *data)
+{
+    AccelClass *ac = ACCEL_CLASS(oc);
+    ac->name = "KVM";
+    ac->init_machine = kvm_init;
+    ac->allowed = &kvm_allowed;
+}
+
+static const TypeInfo kvm_accel_type = {
+    .name = TYPE_KVM_ACCEL,
+    .parent = TYPE_ACCEL,
+    .class_init = kvm_accel_class_init,
+    .instance_size = sizeof(KVMState),
+};
+
+static void kvm_type_init(void)
+{
+    type_register_static(&kvm_accel_type);
+}
+
+type_init(kvm_type_init);
diff --git a/accel/kvm/trace-events b/accel/kvm/trace-events
new file mode 100644
index 0000000000..f89ba5578d
--- /dev/null
+++ b/accel/kvm/trace-events
@@ -0,0 +1,15 @@
+# Trace events for debugging and performance instrumentation
+
+# kvm-all.c
+kvm_ioctl(int type, void *arg) "type 0x%x, arg %p"
+kvm_vm_ioctl(int type, void *arg) "type 0x%x, arg %p"
+kvm_vcpu_ioctl(int cpu_index, int type, void *arg) "cpu_index %d, type 0x%x, arg %p"
+kvm_run_exit(int cpu_index, uint32_t reason) "cpu_index %d, reason %d"
+kvm_device_ioctl(int fd, int type, void *arg) "dev fd %d, type 0x%x, arg %p"
+kvm_failed_reg_get(uint64_t id, const char *msg) "Warning: Unable to retrieve ONEREG %" PRIu64 " from KVM: %s"
+kvm_failed_reg_set(uint64_t id, const char *msg) "Warning: Unable to set ONEREG %" PRIu64 " to KVM: %s"
+kvm_irqchip_commit_routes(void) ""
+kvm_irqchip_add_msi_route(char *name, int vector, int virq) "dev %s vector %d virq %d"
+kvm_irqchip_update_msi_route(int virq) "Updating MSI route virq=%d"
+kvm_irqchip_release_virq(int virq) "virq %d"
+
diff --git a/accel/stubs/Makefile.objs b/accel/stubs/Makefile.objs
new file mode 100644
index 0000000000..bd5794f222
--- /dev/null
+++ b/accel/stubs/Makefile.objs
@@ -0,0 +1 @@
+obj-$(call lnot,$(CONFIG_KVM)) += kvm-stub.o
diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c
new file mode 100644
index 0000000000..ef0c7346af
--- /dev/null
+++ b/accel/stubs/kvm-stub.c
@@ -0,0 +1,158 @@
+/*
+ * QEMU KVM stub
+ *
+ * Copyright Red Hat, Inc. 2010
+ *
+ * Author: Paolo Bonzini     <pbonzini@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "cpu.h"
+#include "sysemu/kvm.h"
+
+#ifndef CONFIG_USER_ONLY
+#include "hw/pci/msi.h"
+#endif
+
+KVMState *kvm_state;
+bool kvm_kernel_irqchip;
+bool kvm_async_interrupts_allowed;
+bool kvm_eventfds_allowed;
+bool kvm_irqfds_allowed;
+bool kvm_resamplefds_allowed;
+bool kvm_msi_via_irqfd_allowed;
+bool kvm_gsi_routing_allowed;
+bool kvm_gsi_direct_mapping;
+bool kvm_allowed;
+bool kvm_readonly_mem_allowed;
+bool kvm_ioeventfd_any_length_allowed;
+bool kvm_msi_use_devid;
+
+int kvm_destroy_vcpu(CPUState *cpu)
+{
+    return -ENOSYS;
+}
+
+int kvm_init_vcpu(CPUState *cpu)
+{
+    return -ENOSYS;
+}
+
+void kvm_flush_coalesced_mmio_buffer(void)
+{
+}
+
+void kvm_cpu_synchronize_state(CPUState *cpu)
+{
+}
+
+void kvm_cpu_synchronize_post_reset(CPUState *cpu)
+{
+}
+
+void kvm_cpu_synchronize_post_init(CPUState *cpu)
+{
+}
+
+int kvm_cpu_exec(CPUState *cpu)
+{
+    abort();
+}
+
+int kvm_has_sync_mmu(void)
+{
+    return 0;
+}
+
+int kvm_has_many_ioeventfds(void)
+{
+    return 0;
+}
+
+int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
+{
+    return -ENOSYS;
+}
+
+int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
+                          target_ulong len, int type)
+{
+    return -EINVAL;
+}
+
+int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
+                          target_ulong len, int type)
+{
+    return -EINVAL;
+}
+
+void kvm_remove_all_breakpoints(CPUState *cpu)
+{
+}
+
+int kvm_on_sigbus_vcpu(CPUState *cpu, int code, void *addr)
+{
+    return 1;
+}
+
+int kvm_on_sigbus(int code, void *addr)
+{
+    return 1;
+}
+
+#ifndef CONFIG_USER_ONLY
+int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev)
+{
+    return -ENOSYS;
+}
+
+void kvm_init_irq_routing(KVMState *s)
+{
+}
+
+void kvm_irqchip_release_virq(KVMState *s, int virq)
+{
+}
+
+int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
+                                 PCIDevice *dev)
+{
+    return -ENOSYS;
+}
+
+void kvm_irqchip_commit_routes(KVMState *s)
+{
+}
+
+int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
+{
+    return -ENOSYS;
+}
+
+int kvm_irqchip_add_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
+                                       EventNotifier *rn, int virq)
+{
+    return -ENOSYS;
+}
+
+int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
+                                          int virq)
+{
+    return -ENOSYS;
+}
+
+bool kvm_has_free_slot(MachineState *ms)
+{
+    return false;
+}
+
+void kvm_init_cpu_signals(CPUState *cpu)
+{
+    abort();
+}
+#endif