On Fri, Jan 24, 2020 at 10:39:16AM -0500, Laine Stump wrote: > Presence of the virtio-net-pci option called "failover" indicates > support in a qemu binary of a simplistic bonding of a virtio-net > device with another PCI device. This feature allows migration of > guests that have a network device assigned to a guest with VFIO, by > creating a network bond device in the guest consisting of the > VFIO-assigned device and a virtio-net-pci device, then temporarily > (and automatically) unplugging the VFIO net device prior to migration > (and hotplugging an equivalent device on the migration > destination). (The feature is called "failover" because the bond > device uses the vfio-pci netdev for normal guest networking, but > "fails over" to the virtio-net-pci netdev once the vfio-pci device is > unplugged for migration.) > > Full functioning of the feature also requires support in the > virtio-net driver in the guest OS (since that is where the bond device > resides), but if the "failover" commandline option is present for the > virtio-net-pci device in qemu, at least the qemu part of the feature > is available, and libvirt can add the proper options to both the > virtio-net-pci and vfio-pci device commandlines to indicate qemu > should attempt doing the failover during migration. > > This patch just adds the qemu capabilities flag "virtio-net.failover". > > Signed-off-by: Laine Stump <laine@xxxxxxxxxx> > --- > > No change from V1. > > src/qemu/qemu_capabilities.c | 4 ++++ > src/qemu/qemu_capabilities.h | 3 +++ > tests/qemucapabilitiesdata/caps_4.2.0.aarch64.xml | 1 + > tests/qemucapabilitiesdata/caps_4.2.0.x86_64.xml | 1 + > 4 files changed, 9 insertions(+) Reviewed-by: Daniel P. Berrangé <berrange@xxxxxxxxxx> Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
