GPU half passed through. Audio portion is vfio-Pci. Graphics driver is Nvidia

Level1Techs
1

I can tell you the whole narrative but the short version is a working GPU passthrough with looking glass setup that has worked for years stopped working after an update.

The problem seems to be no matter what do this is what lspci-k shows me.

01:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX 3080 Lite Hash Rate] (rev a1)
        Subsystem: ASUSTeK Computer Inc. Device 8824
        Kernel driver in use: nvidia
        Kernel modules: nvidiafb, nouveau, nvidia_drm, nvidia
01:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio Controller (rev a1)
        Subsystem: ASUSTeK Computer Inc. Device 8824
        Kernel driver in use: vfio-pci
        Kernel modules: snd_hda_intel

Notice the graphics part of the GPU IS NOT passed through but the Audio part IS. Its like suddenly the procedure that always worked before is now just half working.

I could possibly fix this by blacklisting all Nvidia drivers but that’s not a final solution, since my goal is to get back to where I have two Nvidia GPU’s in the system. The other is a 1080 which I use mainly for compute task and CUDA, while my R75700G is more than enough to run my Linux desktop. That said I could also run it through the Nvidia GPU but you know … Nvidia +Linux has been problems for quite a while.

Any thoughts on what could have caused this?

I did take the chance to test out gaming natively on Linux with it. Got a respectable 70 FPS in Cyberpunk. No ray tracing though. It all looks a lot flatter without it.

EDITED 12/15.

I think I have found the root cause of the issue.

root@yomama:/etc/modprobe.d# sudo update-initramfs -u
update-initramfs: Generating /boot/initrd.img-6.11.0-12-generic
I: The initramfs will attempt to resume from /dev/nvme0n1p3
I: (UUID=da77f558-c7f5-4d3d-8329-a6c638940e58)
I: Set the RESUME variable to override this.
/etc/initramfs-tools/scripts/init-top/vfio-pci-override-vga.sh: 11: echo: echo: I/O error
/etc/initramfs-tools/scripts/init-top/vfio-pci-override-vga.sh: 11: echo: echo: I/O error

SOLUTION:

The solution I have found to at least getting the GPU to be fully passed through again was in total.

Using: GitHub - pavolelsig/passthrough_helper_ubuntu_20: Passthrough helper for Ubuntu 20.04 and 20.10

BUT BUT I had to remove the file [vfio-pci-override-vga.sh]vfio-pci-override-vga.sh

Then I had to run
sudo update-initramfs -u

After posting here I asked Chat GPT 4o for help as well.

Which advised blacklisting all the Nvidia drivers. So when I reinstall the 1080 and try to get it to work while the 3080 is passed that is another sort of problem.

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