Bug#616301: xserver-xorg-video-radeon:screen goes black, system hangs after 2sec:[youtube(FF/Opera)-reset req.]

[Faidon Liambotis]

On Sun, Mar 06, 2011 at 01:08:49PM -0500, Alex Deucher wrote:
> On Fri, Mar 4, 2011 at 8:50 PM, Ben Hutchings <ben at decadent.org.uk> wrote:
> > On Fri, 2011-03-04 at 21:01 +0200, Faidon Liambotis wrote:
> >> This isn't a singled out case nor in exotic, possibly faulty, hardware.
> >> It's on a standard 1½-year old Dell OptiPlex 780 desktop with a Radeon
> >> HD card (one of the standard configurations) and this is on a stock
> >> squeeze system.
> >>
> >> The findings so far seem to suggest this is a Mesa issue; I'd probably
> >> file it under "Linux kernel bugs" (or even DoS bugs) but I'm not sure
> >> where to properly file such bugs in the post-KMS stack world.
> >
> > If there is a kernel driver involved then it should be assigned to the
> > kernel.  Even without KMS, a Mesa driver should be considered untrusted
> > and should not be able to trigger a crash or hang.  With KMS, this
> > applies to the X driver too.
> >
> 
> With or without KMS, the userspace acceleration drivers can certainly
> cause GPU hangs if the 3D engine is programmed with some combination
> of commands it doesn't like.
 
Note that the bug in question causes a *kernel* lockup, not just a GPU
hang. As indicated by the output in the bug log¹, we're getting a “BUG:
unable to handle kernel paging request” after a GPU reset on 2.6.37,
while a silent lockup on 2.6.32.

Regards,
Faidon

¹: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=616301#30