Upgrading my host kernel to
5.7.9 to fix a network stack bug with my system I found that the windows VFIO performance became extremely unstable to the point of being unusable.
The symptoms of this bug as I experienced it:
- Seems to only affect windows guests
- NVidia GPU stalls in the guest, windows performs driver recovery repeatedly.
- Dragging a selection rectangle on the desktop can freeze
- Physical output of the GPU goes black during the GPU recovery.
- BSOD due to failed GPU recovery in the guest.
I have spent the better part of a day tracking this one down, If others have experienced this issue the culprit is this commit that was introduced in
Reverting this commit fixes this behavior.