VM GPU passthrough issues - vfio_region_write failed: Device or resource busy

[ShortbreadUK]

Hi UnRaiders,

I'm getting to the end of my tether with stability of UnRAID, please help or I go back to Windows. I'm having a real issue with GPU passthrough to a Win10 VM. The IOMMU groups and split up quite nicely with my mobo, I dumped my own vbios and I'm referencing that in the VM settings. But when I start the VM up it doesn't show anything and I see a whole lot of this is the VM log:

2018-05-24T13:17:35.701483Z qemu-system-x86_64: vfio_region_write(0000:01:00.0:region0+0xf9788d8, 0x0,8) failed: Device or resource busy

Seems like there is another driver in the host claiming resources or something, but can't manage to fix it. 

Someone please help?

Thanks in advance

serverbread-diagnostics-20180524-1424.zip

 

 

 

 

[MorgothCreator]

Same error here on a Threadripper 1950x a ASRock X399 Taichi board and Nvidia GTX1080TI and Unraid 6.7.2

[Tomway]

I'm having the same error myself, i've tried all kinds of fixes and watched every video SpaceInvaderOne has made about Nvidia GPU passthrough and still no display. I just need it to work temporarily until i can get hold of a RTX 3080 at a non extortionate rate.

 

This is the error code in the log (Log Screenshot Attached)

 

2021-04-05T18:23:12.073130Z qemu-system-x86_64: vfio_region_write(0000:2b:00.0:region3+0x111d780, 0xccff0000ccff,8) failed: Device or resource busy

2021-04-05T18:23:12.074649Z qemu-system-x86_64: vfio_region_write(0000:2b:00.0:region3+0x1121708, 0x0,8) failed: Device or resource busy

 

Unraid 6.9.1

Motherboard: MSI Tomahawk b550 (MS-7c91) Version 2.

CPU: AMD Ryzen 5600x 6-core.

GPU: Nvidia GeForce GTX 650 ti.

RAM: 16gb DDR4 3200mhz.

Latest Bios Installed

I've tried both types of vbios (Hex editing and Script in unraid)

 

All IOMMU Groups passed through successfully and i can boot into GUI Mode! 

 

IOMMU groups enabled in bios as well as VM's

[DesertCookie]

I managed to fix the issue by deleting the VM's log files. It seems like they cannot be written to after I forcefully stopped the VM.

 

I deleted:

/var/log/libvirt/qemu/LOG_NAME

 

[Joseph Higgins]

I can't find that file to delete it....

 

[SimonF]

2 hours ago, Joseph Higgins said:

I can't find that file to delete it....

 

You will have to do from the command line

 

root@computenode:/var/log/libvirt/qemu# ls
HA.log  Unraid-VM.log
root@computenode:/var/log/libvirt/qemu# 

 

[Joseph Higgins]

I used krusader to start with since I don't know the unix command lines at all. I did not think I saw it. Still can't find it.

 

[Joseph Higgins]

My issue was the Nvidia GPU I was attempting to passthrough. I was able to follow the instructions for VM device passthrough in the official documentation. The step I was missing was disabling the GPU in the Bios of the motherboard. It was binding to it on load of Unraid, then I could never pass it through successfully. I was able to play Harry Potter on my 2080ti passed through, although not at the best frame rates. Now I am wondering if I should just move my zzzdarr apps back into windows so that plex has access to the video card again...