How to debug drm/kernel on system freeze

[Alex Deucher]

On Tue, May 3, 2011 at 10:34 AM, Frederik Vogelsang
<frederik.vogelsang at googlemail.com> wrote:
> Hi,
>
> 2011/5/3 Alex Deucher <alexdeucher at gmail.com>:
>> Have you tried a newer kernel, ddx, and mesa?
> yes, I've always been running linux-git, mesa-git, libdrm-git and
> xf86-video-ati-git.
>
> I've experienced this issue for a long time (at least since 2.6.3x),
> so I finally wanted to help out debugging it. It's just that I cannot
> produce *any* debug output on a frozen machine ATM.

The problem with with a lot of lockups is that they don't produce any
special output.

It would help to pinpoint what module is causing the problem.  Try setting:
Option "NoAccel" "True"
in the device section of your xorg.conf.  That will disable all acceleration.
Next you can try removing that option and disabling EXA composite:
Option "EXANoComposite" "true"

If you are using 3D acceleration, try r300g rather than r300c.

Alex