Bug#1114912: Bug troubleshooting

[Naunte <dec01-2021@hotmail.com>]

On Tue, 23 Sep 2025 00:55:40 +0000 Christopher W <sun-chris@outlook.com> 
wrote:
> I experienced this same bug, and in my troubleshooting worked around 
it with the following steps:
>
> 1. Added
>     vfio_pci.ids=[pair of Radeon 6800 ids here]
>     to my cmdline
> 2. Added
>     softdep drm pre: vfio-pci
>     to new file /etc/modprobe.d/vfio.conf
> 3. Regenerate initramfs
>
> Making vfio-pci load before amdgpu at boot, so that it can 
effectively get bound to the GPU instead of amdgpu as specified by the 
cmdline argument
>
> Since the bug occurs when the host attempts to reclaim the GPU from a 
VM with the amdgpu driver, adjusting it so that the host never loads 
amdgpu on it and always has the card on vfio-pci prevents all hanging 
and errors. Allowing for it to be freely booted with another VMs after 
the VM using it shuts down
>
> This works as a solution on my setup where the host uses the CPU's 
iGPU for its display output, and uses the discrete GPU exclusively for 
passthrough to VMs. But this wouldn't work on a system where there's 
only one GPU and single GPU passthrough is being done Here is the 
translated and grammar-optimized English version:

***

Hi Christopher,
Thank you for your reply and suggestions. However, the parameters 
`vfio_pci.ids=` and `softdep drm pre: vfio-pci` are not available on 
Debian 13. Instead, it is necessary to use `options vfio-pci ids=` and 
either `softdep drm pre: vfio-pci` or `softdep amdgpu pre: vfio-pci`.

This is indeed a temporary workable solution. Since I need to switch the 
GPU between different VMs, although it is possible to automate the 
switching via scripts, it would be best if native support and switching 
were available without the reset bug.

Regards,

Naunte