[vfio-users] AMD reset bug on rx 480

[Nick S]

I think I was able to mitigate the issue by ejecting the GPU and switching
to qemu emulated graphics before the shutdown and then reverting this
process after a restart. I am fairly sure it all started with 17.12.02
version of Radeon drivers. 17.10.02 seems to be working fine. Did we get
the reset bug back via a software upgraded and even on the cards where it
did not happen before?

2017-12-26 14:06 GMT-08:00 Nick S <nick.kvmhv at gmail.com>:

> I have several RX 480 cards that I use to run virtual machines and one of
> them is getting bugged intermittently after several virtual machine
> restarts. When it happens, the screen either turns off or turns light grey
> and Windows 7 or 10 just BSOD repeatedly when starting. The only thing that
> helps consistently is restarting the entire PC. Once I was able to fix the
> card by doing the following:
>
> 1) Pull and reinsert the PCIE 6 pin power cable from it
> 2) Unbind card from vfio driver
> 3) echo "1" > /sys/bus/pci/devices/MY:CARD:NUMBER/remove
> 4) echo "1" > /sys/bus/pci/rescan
>
> Just steps 2 through 4 do not seem to help and I am a bit hesitant messing
> with cables on a running PC.
>
> Question: is there a way to reset the card without a restart? I get this
> situation fairly infrequently, but still it is a bit annoying. Also, would
> it make sense to add my card to pci-quirks.c where it handles older cards?
> There is no polaris cards there as far as I can see.
>
>
>
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