graphic: 0.894
other: 0.847
boot: 0.842
semantic: 0.800
device: 0.798
mistranslation: 0.784
network: 0.650
instruction: 0.611
KVM: 0.596
socket: 0.556
assembly: 0.466
vnc: 0.440

vfio-pci passthrough issue after resume from suspend


I'm running into a weird issue with the vfio-pci driver through qemu

I use it on a laptop and I passthrough an external GPU connected via PCI express. In general this works well, however if the laptop has *ever* suspended since its last boot, then the windows guest reports an error 43 on the card and I get no output on the monitor that it is connected to. This is really weird to me since it works fine if I boot the latop from power-off, and hotplug the card. It's only if the laptop has ever suspended since it's last boot that I see this issue. Even if it was suspended before the card was ever hotplugged. 

In other words:
laptop off -> boot -> hotplug GPU : works great
laptop off -> boot -> do stuff (GPU *NOT* connected) -> sleep -> resume -> hotplug GPU: problem
laptop off -> boot -> hotplug GPU -> unplug GPU -> hotplug GPU : works great
laptop off -> boot -> hotplug GPU -> unplug GPU -> sleep -> resume -> hotplug GPU: problem

Weird stuff...

I'm honestly not sure that vfio-pci/qemu is to blame here since there are so many moving parts, but im not really sure where else to report this to

What I have tried is using the sysfs interface to remove/rescan/poweroff/etc the PCI devices in questions (graphics card and it's HDMI audio) and this also does help.

QEMU version: 2.6.1

Please let me know what other information I can provide

The QEMU project is currently considering to move its bug tracking to another system. For this we need to know which bugs are still valid and which could be closed already. Thus we are setting all older bugs to
"Incomplete" now.
If you still think this bug report here is valid, then please switch the state back to "New" within the next 60 days, otherwise this report will be marked as "Expired". Thank you and sorry for the inconvenience.


I don't use this setup anymore so I don't know if it's still an issue, it would have been nice if someone had responded to my report when I filed it over 3 years ago. Go ahead and close it.

Thanks for your answer, and sorry that nobody replied to your original report - sometimes there is just no expert around, or nobody has a clue about the right answer... anyway, let's close this ticket now.