https://bugzilla.kernel.org/show_bug.cgi?id=38792
--- Comment #8 from Alex Deucher alexdeucher@gmail.com 2011-08-25 22:07:08 --- As I said before, this is most likely a bug in the ddx or 3D driver. The drm is doing what it's supposed to do: resetting the GPU when it detects a hang. Does upgrading mesa or xf86-video-ati help? I'd suggest mesa 7.11 or git master.