From 35c7cb4caff66fe4c01711243d42de4445cb83e2 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Wed, 22 Feb 2017 13:19:58 -0700 Subject: vfio/pci: Report errors from qdev_unplug() via device request MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently we ignore this error, report it with error_reportf_err() Signed-off-by: Alex Williamson Reviewed-by: Eric Auger Reviewed-by: Philippe Mathieu-Daudé --- hw/vfio/pci.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'hw') diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 332f41d662..f2ba9b6cfa 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -2506,12 +2506,16 @@ static void vfio_unregister_err_notifier(VFIOPCIDevice *vdev) static void vfio_req_notifier_handler(void *opaque) { VFIOPCIDevice *vdev = opaque; + Error *err = NULL; if (!event_notifier_test_and_clear(&vdev->req_notifier)) { return; } - qdev_unplug(&vdev->pdev.qdev, NULL); + qdev_unplug(&vdev->pdev.qdev, &err); + if (err) { + error_reportf_err(err, WARN_PREFIX, vdev->vbasedev.name); + } } static void vfio_register_req_notifier(VFIOPCIDevice *vdev) -- cgit v1.2.3 From d0d1cd70d10639273e2a23870e7e7d80b2bc4e21 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Wed, 22 Feb 2017 13:19:58 -0700 Subject: vfio/pci: Improve extended capability comments, skip masked caps Since commit 4bb571d857d9 ("pci/pcie: don't assume cap id 0 is reserved") removes the internal use of extended capability ID 0, the comment here becomes invalid. However, peeling back the onion, the code is still correct and we still can't seed the capability chain with ID 0, unless we want to muck with using the version number to force the header to be non-zero, which is much uglier to deal with. The comment also now covers some of the subtleties of using cap ID 0, such as transparently indicating absence of capabilities if none are added. This doesn't detract from the correctness of the referenced commit as vfio in the kernel also uses capability ID zero to mask capabilties. In fact, we should skip zero capabilities precisely because the kernel might also expose such a capability at the head position and re-introduce the problem. Signed-off-by: Alex Williamson Reviewed-by: Peter Xu Tested-by: Peter Xu Reported-by: Jintack Lim Tested-by: Jintack Lim --- hw/vfio/pci.c | 31 +++++++++++++++++++++---------- 1 file changed, 21 insertions(+), 10 deletions(-) (limited to 'hw') diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index f2ba9b6cfa..03a3d01549 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -1880,16 +1880,26 @@ static void vfio_add_ext_cap(VFIOPCIDevice *vdev) /* * Extended capabilities are chained with each pointing to the next, so we * can drop anything other than the head of the chain simply by modifying - * the previous next pointer. For the head of the chain, we can modify the - * capability ID to something that cannot match a valid capability. ID - * 0 is reserved for this since absence of capabilities is indicated by - * 0 for the ID, version, AND next pointer. However, pcie_add_capability() - * uses ID 0 as reserved for list management and will incorrectly match and - * assert if we attempt to pre-load the head of the chain with this ID. - * Use ID 0xFFFF temporarily since it is also seems to be reserved in - * part for identifying absence of capabilities in a root complex register - * block. If the ID still exists after adding capabilities, switch back to - * zero. We'll mark this entire first dword as emulated for this purpose. + * the previous next pointer. Seed the head of the chain here such that + * we can simply skip any capabilities we want to drop below, regardless + * of their position in the chain. If this stub capability still exists + * after we add the capabilities we want to expose, update the capability + * ID to zero. Note that we cannot seed with the capability header being + * zero as this conflicts with definition of an absent capability chain + * and prevents capabilities beyond the head of the list from being added. + * By replacing the dummy capability ID with zero after walking the device + * chain, we also transparently mark extended capabilities as absent if + * no capabilities were added. Note that the PCIe spec defines an absence + * of extended capabilities to be determined by a value of zero for the + * capability ID, version, AND next pointer. A non-zero next pointer + * should be sufficient to indicate additional capabilities are present, + * which will occur if we call pcie_add_capability() below. The entire + * first dword is emulated to support this. + * + * NB. The kernel side does similar masking, so be prepared that our + * view of the device may also contain a capability ID zero in the head + * of the chain. Skip it for the same reason that we cannot seed the + * chain with a zero capability. */ pci_set_long(pdev->config + PCI_CONFIG_SPACE_SIZE, PCI_EXT_CAP(0xFFFF, 0, 0)); @@ -1915,6 +1925,7 @@ static void vfio_add_ext_cap(VFIOPCIDevice *vdev) PCI_EXT_CAP_NEXT_MASK); switch (cap_id) { + case 0: /* kernel masked capability */ case PCI_EXT_CAP_ID_SRIOV: /* Read-only VF BARs confuse OVMF */ case PCI_EXT_CAP_ID_ARI: /* XXX Needs next function virtualization */ trace_vfio_add_ext_cap_dropped(vdev->vbasedev.name, cap_id, next); -- cgit v1.2.3 From c2b2e158cc7b1cb431bd6039824ec13c3184a775 Mon Sep 17 00:00:00 2001 From: XiongZhang Date: Wed, 22 Feb 2017 13:19:59 -0700 Subject: vfio/pci-quirks.c: Disable stolen memory for igd VFIO Regardless of running in UPT or legacy mode, the guest igd drivers may attempt to use stolen memory, however only legacy mode has BIOS support for reserving stolen memmory in the guest VM. We zero out the stolen memory size in all cases, then guest igd driver won't use stolen memory. In legacy mode, user could use x-igd-gms option to specify the amount of stolen memory which will be pre-allocated and reserved by bios for igd use. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99028 https://bugs.freedesktop.org/show_bug.cgi?id=99025 Signed-off-by: Xiong Zhang Tested-by: Terrence Xu Signed-off-by: Alex Williamson --- hw/vfio/pci-quirks.c | 65 ++++++++++++++++++++++++++++++---------------------- 1 file changed, 38 insertions(+), 27 deletions(-) (limited to 'hw') diff --git a/hw/vfio/pci-quirks.c b/hw/vfio/pci-quirks.c index e9b493b939..e995e32dee 100644 --- a/hw/vfio/pci-quirks.c +++ b/hw/vfio/pci-quirks.c @@ -1367,14 +1367,45 @@ static void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr) uint16_t cmd_orig, cmd; Error *err = NULL; + /* This must be an Intel VGA device. */ + if (!vfio_pci_is(vdev, PCI_VENDOR_ID_INTEL, PCI_ANY_ID) || + !vfio_is_vga(vdev) || nr != 4) { + return; + } + /* - * This must be an Intel VGA device at address 00:02.0 for us to even - * consider enabling legacy mode. The vBIOS has dependencies on the - * PCI bus address. + * IGD is not a standard, they like to change their specs often. We + * only attempt to support back to SandBridge and we hope that newer + * devices maintain compatibility with generation 8. */ - if (!vfio_pci_is(vdev, PCI_VENDOR_ID_INTEL, PCI_ANY_ID) || - !vfio_is_vga(vdev) || nr != 4 || - &vdev->pdev != pci_find_device(pci_device_root_bus(&vdev->pdev), + gen = igd_gen(vdev); + if (gen != 6 && gen != 8) { + error_report("IGD device %s is unsupported by IGD quirks, " + "try SandyBridge or newer", vdev->vbasedev.name); + return; + } + + /* + * Regardless of running in UPT or legacy mode, the guest graphics + * driver may attempt to use stolen memory, however only legacy mode + * has BIOS support for reserving stolen memory in the guest VM. + * Emulate the GMCH register in all cases and zero out the stolen + * memory size here. Legacy mode may request allocation and re-write + * this below. + */ + gmch = vfio_pci_read_config(&vdev->pdev, IGD_GMCH, 4); + gmch &= ~((gen < 8 ? 0x1f : 0xff) << (gen < 8 ? 3 : 8)); + + /* GMCH is read-only, emulated */ + pci_set_long(vdev->pdev.config + IGD_GMCH, gmch); + pci_set_long(vdev->pdev.wmask + IGD_GMCH, 0); + pci_set_long(vdev->emulated_config_bits + IGD_GMCH, ~0); + + /* + * This must be at address 00:02.0 for us to even onsider enabling + * legacy mode. The vBIOS has dependencies on the PCI bus address. + */ + if (&vdev->pdev != pci_find_device(pci_device_root_bus(&vdev->pdev), 0, PCI_DEVFN(0x2, 0))) { return; } @@ -1393,18 +1424,6 @@ static void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr) return; } - /* - * IGD is not a standard, they like to change their specs often. We - * only attempt to support back to SandBridge and we hope that newer - * devices maintain compatibility with generation 8. - */ - gen = igd_gen(vdev); - if (gen != 6 && gen != 8) { - error_report("IGD device %s is unsupported in legacy mode, " - "try SandyBridge or newer", vdev->vbasedev.name); - return; - } - /* * Most of what we're doing here is to enable the ROM to run, so if * there's no ROM, there's no point in setting up this quirk. @@ -1460,8 +1479,6 @@ static void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr) goto out; } - gmch = vfio_pci_read_config(&vdev->pdev, IGD_GMCH, 4); - /* * If IGD VGA Disable is clear (expected) and VGA is not already enabled, * try to enable it. Probably shouldn't be using legacy mode without VGA, @@ -1532,12 +1549,11 @@ static void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr) * when IVD (IGD VGA Disable) is clear, but the claim is that it's unused, * so let's not waste VM memory for it. */ - gmch &= ~((gen < 8 ? 0x1f : 0xff) << (gen < 8 ? 3 : 8)); - if (vdev->igd_gms) { if (vdev->igd_gms <= 0x10) { gms_mb = vdev->igd_gms * 32; gmch |= vdev->igd_gms << (gen < 8 ? 3 : 8); + pci_set_long(vdev->pdev.config + IGD_GMCH, gmch); } else { error_report("Unsupported IGD GMS value 0x%x", vdev->igd_gms); vdev->igd_gms = 0; @@ -1557,11 +1573,6 @@ static void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr) fw_cfg_add_file(fw_cfg_find(), "etc/igd-bdsm-size", bdsm_size, sizeof(*bdsm_size)); - /* GMCH is read-only, emulated */ - pci_set_long(vdev->pdev.config + IGD_GMCH, gmch); - pci_set_long(vdev->pdev.wmask + IGD_GMCH, 0); - pci_set_long(vdev->emulated_config_bits + IGD_GMCH, ~0); - /* BDSM is read-write, emulated. The BIOS needs to be able to write it */ pci_set_long(vdev->pdev.config + IGD_BDSM, 0); pci_set_long(vdev->pdev.wmask + IGD_BDSM, ~0); -- cgit v1.2.3