[PATCH] drm/amd/powerplay: don't give up if DPM is already running

[Grazvydas Ignotas]

Hi,

On Thu, Oct 13, 2016 at 10:45 AM, Zhu, Rex <Rex.Zhu at amd.com> wrote:
>
> The attached patches were also for this issue.
> Disable dpm when rmmod amdgpu.

It works for modprobe-rmmod-modprobe test, thanks.

However with GPU passthrough (giving control of the GPU to a Windows
virtual machine using iommu, then shutting down the VM and loading
amdgpu) the problem is still there, same backtrace as in my commit
message. It seems the Windows driver leaves DPM enabled on shutdown.
With my patch the crash goes away.

It would be nice to have GPU passthrough working, this is the only
issue that breaks it. Windows can drive the GPU after amdgpu fine
already, only amdgpu has problems to run after Windows.

Gražvydas