diff options
Diffstat (limited to 'hw/virtio')
| -rw-r--r-- | hw/virtio/virtio-pci.c | 29 | ||||
| -rw-r--r-- | hw/virtio/virtio-pci.h | 5 |
2 files changed, 16 insertions, 18 deletions
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index e490ade..dde1d73 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -86,9 +86,6 @@ * 12 is historical, and due to x86 page size. */ #define VIRTIO_PCI_QUEUE_ADDR_SHIFT 12 -/* Flags track per-device state like workarounds for quirks in older guests. */ -#define VIRTIO_PCI_FLAG_BUS_MASTER_BUG (1 << 0) - static void virtio_pci_bus_new(VirtioBusState *bus, size_t bus_size, VirtIOPCIProxy *dev); @@ -323,14 +320,6 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) proxy->pci_dev.config[PCI_COMMAND] | PCI_COMMAND_MASTER, 1); } - - /* Linux before 2.6.34 sets the device as OK without enabling - the PCI device bus master bit. In this case we need to disable - some safety checks. */ - if ((val & VIRTIO_CONFIG_S_DRIVER_OK) && - !(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) { - proxy->flags |= VIRTIO_PCI_FLAG_BUS_MASTER_BUG; - } break; case VIRTIO_MSI_CONFIG_VECTOR: msix_vector_unuse(&proxy->pci_dev, vdev->config_vector); @@ -483,8 +472,7 @@ static void virtio_write_config(PCIDevice *pci_dev, uint32_t address, pci_default_write_config(pci_dev, address, val, len); if (range_covers_byte(address, len, PCI_COMMAND) && - !(pci_dev->config[PCI_COMMAND] & PCI_COMMAND_MASTER) && - !(proxy->flags & VIRTIO_PCI_FLAG_BUS_MASTER_BUG)) { + !(pci_dev->config[PCI_COMMAND] & PCI_COMMAND_MASTER)) { virtio_pci_stop_ioeventfd(proxy); virtio_set_status(vdev, vdev->status & ~VIRTIO_CONFIG_S_DRIVER_OK); } @@ -895,11 +883,15 @@ static void virtio_pci_vmstate_change(DeviceState *d, bool running) VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); if (running) { - /* Try to find out if the guest has bus master disabled, but is - in ready state. Then we have a buggy guest OS. */ - if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) && + /* Old QEMU versions did not set bus master enable on status write. + * Detect DRIVER set and enable it. + */ + if ((proxy->flags & VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION) && + (vdev->status & VIRTIO_CONFIG_S_DRIVER) && !(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) { - proxy->flags |= VIRTIO_PCI_FLAG_BUS_MASTER_BUG; + pci_default_write_config(&proxy->pci_dev, PCI_COMMAND, + proxy->pci_dev.config[PCI_COMMAND] | + PCI_COMMAND_MASTER, 1); } virtio_pci_start_ioeventfd(proxy); } else { @@ -1040,10 +1032,11 @@ static void virtio_pci_reset(DeviceState *qdev) virtio_pci_stop_ioeventfd(proxy); virtio_bus_reset(bus); msix_unuse_all_vectors(&proxy->pci_dev); - proxy->flags &= ~VIRTIO_PCI_FLAG_BUS_MASTER_BUG; } static Property virtio_pci_properties[] = { + DEFINE_PROP_BIT("virtio-pci-bus-master-bug-migration", VirtIOPCIProxy, flags, + VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION_BIT, false), DEFINE_VIRTIO_COMMON_FEATURES(VirtIOPCIProxy, host_features), DEFINE_PROP_END_OF_LIST(), }; diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h index 1cea157..8873b6d 100644 --- a/hw/virtio/virtio-pci.h +++ b/hw/virtio/virtio-pci.h @@ -53,6 +53,11 @@ typedef struct VirtioBusClass VirtioPCIBusClass; #define VIRTIO_PCI_BUS_CLASS(klass) \ OBJECT_CLASS_CHECK(VirtioPCIBusClass, klass, TYPE_VIRTIO_PCI_BUS) +/* Need to activate work-arounds for buggy guests at vmstate load. */ +#define VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION_BIT 0 +#define VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION \ + (1 << VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION_BIT) + /* Performance improves when virtqueue kick processing is decoupled from the * vcpu thread using ioeventfd for some devices. */ #define VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT 1 |