The intend of failover is to allow to migrate a VM with a VFIO networking card without disrupting the network operation by switching to a virtio-net device during the migration.
This simple change allows to test failover with a simulated device like e1000e rather than a vfio device, even if it's useless in real life it can help to debug failover. This is interesting to developers that want to test failover on a system with no vfio device. Moreover it simplifies host networking configuration as we can use the same bridge for virtio-net and the other failover networking device. Without this change the migration of a system configured with failover fails with: ... -device virtio-net-pci,id=virtionet0,failover=on,... \ -device e1000,failover_pair_id=virtionet0,... \ ... (qemu) migrate ... Unknown ramblock "0000:00:01.1:00.0/e1000e.rom", cannot accept migration error while loading state for instance 0x0 of device 'ram' load of migration failed: Invalid argument This happens because QEMU correctly unregisters the interface vmstate but not the ROM one. This patch fixes that. Signed-off-by: Laurent Vivier <[email protected]> --- Notes: v4: export and use pci_del_option_rom() v3: remove useless space before comma v2: reset has_rom to false update commit log message include/hw/pci/pci.h | 2 ++ hw/net/virtio-net.c | 1 + hw/pci/pci.c | 3 +-- 3 files changed, 4 insertions(+), 2 deletions(-) diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h index d0f4266e3725..84707034cbf8 100644 --- a/include/hw/pci/pci.h +++ b/include/hw/pci/pci.h @@ -369,6 +369,8 @@ void pci_register_vga(PCIDevice *pci_dev, MemoryRegion *mem, void pci_unregister_vga(PCIDevice *pci_dev); pcibus_t pci_get_bar_addr(PCIDevice *pci_dev, int region_num); +void pci_del_option_rom(PCIDevice *pdev); + int pci_add_capability(PCIDevice *pdev, uint8_t cap_id, uint8_t offset, uint8_t size, Error **errp); diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 16d20cdee52a..d6f03633f1b3 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -3256,6 +3256,7 @@ static void virtio_net_handle_migration_primary(VirtIONet *n, MigrationState *s) if (migration_in_setup(s) && !should_be_hidden) { if (failover_unplug_primary(n, dev)) { vmstate_unregister(VMSTATE_IF(dev), qdev_get_vmsd(dev), dev); + pci_del_option_rom(PCI_DEVICE(dev)); qapi_event_send_unplug_primary(dev->id); qatomic_set(&n->failover_primary_hidden, true); } else { diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 23d2ae2ab232..c210d92b5ba7 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -228,7 +228,6 @@ static PCIBus *pci_find_bus_nr(PCIBus *bus, int bus_num); static void pci_update_mappings(PCIDevice *d); static void pci_irq_handler(void *opaque, int irq_num, int level); static void pci_add_option_rom(PCIDevice *pdev, bool is_default_rom, Error **); -static void pci_del_option_rom(PCIDevice *pdev); static uint16_t pci_default_sub_vendor_id = PCI_SUBVENDOR_ID_REDHAT_QUMRANET; static uint16_t pci_default_sub_device_id = PCI_SUBDEVICE_ID_QEMU; @@ -2429,7 +2428,7 @@ static void pci_add_option_rom(PCIDevice *pdev, bool is_default_rom, pci_register_bar(pdev, PCI_ROM_SLOT, 0, &pdev->rom); } -static void pci_del_option_rom(PCIDevice *pdev) +void pci_del_option_rom(PCIDevice *pdev) { if (!pdev->has_rom) return; -- 2.31.1
