[SOLVED] Windows 10 VM with PCI passthrough doesn't see the passed device

[brewsomecoffee]

Hi, I'm super new to Proxmox, I've searched the forums but not found anything that got me out of the hole I'm in. I have a Windows VM I'd like to use an AMD 7900 GRE GPU as a passthrough device. So far, I have done all this, based on some forum posts, some of which is probably redundant:

from /etc/modprobe/blacklist.conf:

blacklist amdgpu

from /etc/modules:

vfio
vfio_iommu_type1
vfio_pci
vfio_virqfd

from /etc/default/grub:

GRUB_CMDLINE_LINUX_DEFAULT="quiet amd_iommu=on iommu=pt initcall_blacklist=sysfb_init vfio-pci.ids=1002:744c,1002:ab30"
GRUB_CMDLINE_LINUX="textonly video=astdrmfb video=efifb:off"

from /etc/modprobe.d/vfio.conf:

softdep i2c_designware_pci pre: vfio-pci
softdep xhci_pci pre: vfio-pci
softdep snd_hda_intel pre: vfio-pci
softdep amdgpu pre: vfio-pci
options vfio-pci ids=1002:744c,1002:ab30 disable_vga=1

From there, I did a raw mapping of the GPU to a Windows 10 VM; I tried a few permutations, e.g. with and without "all functions", "pci-express", but the Windows VM never saw the card show up in Device Manager.

I tried a Linux VM, a Fedora 39 bare install, and using the same process, I was able to at least get the GPU to show up in `lspci` in the VM.

Anyone have ideas what I might be missing?

Thanks!

 

[VMler]

Greetings, i ran into similar issues with my new 7840HS mini-pc (with Radeon 780 Graphics). The steps that you have taken so far are correct: blacklisting the drivers, configuring vfio, altering the grub boot options. After hours and hours of trying (and searching) i found out that there are a few more steps to do:

1. You need to read out the vbios and present it to the guests config-file as a "romfile" as described here (vbios.c): Guide at Github (Ryzen GPUs in Proxmox Guests) (credits out to Ivan Sanz Carasa "isc30").

2. After you see the GPU in Windows, you might get the "Error 43" in Device Manager: as i found out, this problem is related to no active/connected display to the graphics port. In simple words: the GPU would not get active when no display is connected. As a workaround simply connect a monitor to your graphics port. Meanwhile my "solution" is a so called "HDMI ghost adapter" which you can get from the great online shopping company for a few bucks. Mine is the 1440p-Version which works great (even with 1080p resolution)!

3. If you try to install AMDs Adrenalin driver, the setup aborts with "Error: No AMD hardware detected." Delete the setup-file and get the "offline"-package (650 MB+) from AMDs dl-page, this does the trick!

4. When everything is fine and you enjoyed your Windows-Session, the whole Proxmox-Host will crash if you shutdown the Windows guest. This problem is related to the "AMD reset bug". To fix this, you need to install the following program to your windows machine: nga-lovinde: AMD Reset Bug fix (credits out to "inga-lovinde").


With all this applied, my Proxmox "Gaming VM" runs perfectly.

Good luck!

 

[brewsomecoffee]

Thanks! I did not have to dump and load my rom, but I did have to use the "offline" gpu installer, it looks happy now!

 

[VMler]

Nice to read, you're welcome!

 

[thebuildingguy]

@brewsomecoffee did you face any reset issue with this gpu

can you do one thing, start/stop the windows vm with the gpu + driver multiple times let say 4 times and then on 5th attempt run furmark or a game or passmark full and see if gpu crash or you see any error on dmesg

Do the start stop from proxmox like a hardstop not a Shutdown

Also is your RESIZEABLE BAR enabled in BIOS ?