Nvidia GPU Passthrough with vbios - No Display with VM's (System Log and Diagnostics Attached!)

[Tomway]

Hey hows it going, my name is Tom. I've recently started using Unraid because it is the best solution out there for running a Media Server, File Storage and Virtual Machines.

 

I've tried all kinds of fixes and watched every video SpaceInvaderOne has made about Nvidia GPU passthrough, vbios dumping and I've still got no display output. I was using legacy boot which was working okay for Unraid but the graphics on the GUI mode was a bit out of whack, so i started using UEFI boot and that sorted out the graphics on the GUI Mode and normal boot mode. Just still no GPU Passthrough with VM's.

 

What's strange is that Unraid can boot into GUI Mode just fine using the GPU in slot 1, but won't passthrough on a Windows 10 or any other type of VM.

 

When starting up a VM (Win10 in this case) bellow is the error im getting on the log. (Screenshot also attached)

 

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. (No On-Board Graphics)

GPU: Nvidia GeForce GTX 650 ti. (Slot 1)

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

 

DIagnostics and SYS Log Uploaded!

 

I just need it to work temporarily until i can get hold of a RTX 3080 at a non extortionate rate.

 

NVIDIA.GTX650Ti.2048.121108.rom scarif-diagnostics-20210405-2053.zip scarif-syslog-20210405-1948.zip GTX650vbios.rom

[NomadicAgriculturalist]

Hey Tomway,

 

Hopefully, you've figured out a solution by now, i.e. went back to using legacy boot. I'm not sure how your setup is intended to work, but it appears Unraid couldn't passthrough your GPU because it was already allocated to the GUI. That being said, I myself started using Unraid last year and have never booted into GUI mode, so am not sure why you do. I would suggest two solutions for you:
1) Stop using GUI mode. Use legacy boot and control your Unraid system through a web browser running on a local device on your network. This is how most people appear to use Unraid. If you don't have access to a laptop, 2nd desktop, etc, you can probably get away with using a phone connected to the same wifi network, at least for startup. Afterwards, you can technically manage Unraid through a web browser within a VM.
2) If you really need to access Unraid through the GUI for whatever reason, you'll probably need to put another GPU in the primary PCI-E slot for GUI mode to boot to and run off. This can be a cheap, low-end GPU.

 

Hope that helps.

 

The only reason I stumbled upon this page was because I encountered the same "...qemu-system-x86_64: vfio_region_write(...) failed: Device or resource busy" error. Reading this post, helped me troubleshoot my own problems. My motherboard detects two boot options on my Unraid flash drive, a legacy one and a uefi one. Turns out I switched the boot order/preference after messing around with some settings in the motherboard bios. So, if anyone happens to stumble upon this page in the future, running a single-GPU system with passthrough to a VM and all of a sudden encounters this error, try clicking your boot device on the Main tab and make sure "Server boot mode" displays "legacy". Spent several hours troubleshooting my system until I came across this post, thanks!