Regression with kernel 4.20 on armhf

[Michel Dänzer]

On 2019-01-04 4:32 p.m., Luís Mendes wrote:
> Hi Alex, Christian,
> 
> I've tested amd-staging-drm-next at commit
> 9698024e8a191481321574bec1fe886bbce797cf - drm/amdgpu: Cleanup 2
> compiler warnings,
> and now RX 550 Polaris 12 still hangs in ring gfx with XOrg, but a gpu
> recovery is now performed and works, except that VRAM contents are
> lost and screen image becomes corrupted.

This is because OpenGL contexts become unusable when a full GPU reset is
performed. Making it possible to fully recover from this without
restarting Xorg (which uses OpenGL via glamor) or at least the
compositor / other apps using OpenGL would be tricky and require a lot
of effort, so I wouldn't bet on it ever happening I'm afraid.


> Maybe this is not a driver issue, but rather a mesa or XOrg issue,
> since something is sent to the compute/gfx unit that causes the GPU to
> hang, so it is not only timing sensitive, but is mainly because of
> wrong openGL commands, that drive the GPU into an invalid state

In that case, the problem would be expected to happen the same way on
x86 as well. There seems to be some kind of platform specific aspect
affecting it.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer