https://git.qemu.org/?p=qemu.git;a=commitdiff;h=0446f8121723b134ca1d1ed0b73e96d4a0a8689d;hp=48008198270e3ebcc9394401d676c54ed5ac139cWe've also noticed that if the vfio device of the pair is manually unplugged from the guest, the DEVICE_DELETED event never makes it back up to libvirt, and so the device isn't removed from the libvirt config for the guest, is marked as still in-use, and can't be re-plugged into the same or any other guest until that particular guest is shut down. We still haven't found the root cause of that problem, but it seems likely it's not in these patches (more likely an issue in qemu or in the guest), so I posted them :-)
I forgot to mention in the cover letter - there is a bug in the QEMU
4.2.0 release that causes the qemu process to crash whenever the vfio
device is unplugged, and for some reason when booting a Fedora 31 guest
with a failover pair, the guest kernel attempts to unplug the vfio
device during its initial boot! Fortunately that bug is already fixed,
by this qemu commit:
- [libvirt PATCH 08/12] conf: add backupAlias attribute... Laine Stump
- Re: [libvirt PATCH 08/12] conf: add backupAlias ... Daniel P . Berrangé
- [libvirt PATCH 11/12] docs: document virtio failover ... Laine Stump
- [libvirt PATCH 05/12] qemu: add capabilities flag for... Laine Stump
- [libvirt PATCH 12/12] conf/qemu: new <driver> a... Laine Stump
- Re: [libvirt PATCH 12/12] conf/qemu: new <dri... Daniel P . Berrangé
- Re: [libvirt PATCH 12/12] conf/qemu: new <... Dan Kenigsberg
- Re: [libvirt PATCH 12/12] conf/qemu: new... Daniel P . Berrangé
- Re: [libvirt PATCH 12/12] conf/qemu:... Dan Kenigsberg
- Re: [libvirt PATCH 12/12] conf/... Daniel P . Berrangé
- Re: [libvirt PATCH 00/12] virtio failover / vfio auto... Laine Stump