Windows 11 VM freezes randomly when PCI passthrough

[vamitrou]

Hi there -

 

It's been weeks already me trying to debug the situation. I have a Windows 11 VM as my daily driver which randomly freezes (mostly when unused). When this happens I can see the assigned CPU cores are maxing out in the Unraid dashboard. 

 

I have tried different configurations and it seems that this behavior only occurs when passing through my RTX3070 GPU. I have observed that without passing through the GPU and any PCI or USB device the system works fine. 

 

I really have no idea what to look next. Any advise is greatly appreciated.  

box-diagnostics-20230519-1218.zip

[ghost82]

May be caused by virtiofs; try to stop using this and use a samba share for example and see if the crashes stop.

[vamitrou]

Thanks so much! Indeed, the virtiofs and specifically the memory backing causes this issue. Removing that from my XML resolves the issue. 

 

Bug report on qemu: https://gitlab.com/qemu-project/qemu/-/issues/1270 

[MrBrac]

according to that bug report , we would need qemu 7.2 to use VirtioFS since it seems to be fixed in 7.2. updated to RC 1 of 6.12.5 and it has 7.2. So farm my VM is running smoother no freeze about 30
+mins in now

Edited November 27, 2023 by MrBrac

[MrBrac]

Yep after all this time my VM is now running and running erstatz while before it would die in like 30 mins. Atm its been hours. So if you have this issue , id recommend updating to RC1 and and pushing to Qemu 7.2.

[vamitrou]

Thanks for the feedback. I tried it myself with 6.12.6 and it works indeed. However, I can see increase in CPU usage and drops my FPS significantly during gaming. Regardless if I load my games from that particular disk or not. WinFSP and VirtioFS were also disabled in some of the tests. 

Edited December 10, 2023 by vamitrou