Bug#637958: X.org crash leaves GPU in an inconsistent state and renders system unbootable

[Michel Dänzer]

On Don, 2011-08-25 at 09:50 +0100, Martin wrote: 
> On Wed, 2011-08-24 at 08:50 +0200, Michel Dänzer wrote:
> > On Die, 2011-08-23 at 23:14 +0100, Martin wrote: 
> > > 
> > > Right; have upgraded to the latest X.org and kernel in backports and the
> > > problem still persists.  Something causes the machine to hang while
> > > bieng used interactively in X and after this loading the kernel psmouse
> > > module hangs the machine.
> > > 
> > > What should I try next?
> > 
> > Can you try if the hangs in X happen when the psmouse module is never
> > loaded in the first place?
> 
> So I've tried the following:
> 
> 1. Boot from a Debian 4.0 install CD to clear the non-volatile fault.
> 
> 2. Boot from a Debian 6.0 install CD to blacklist psmouse without
> loading it.
> 
> 3. Reboot the system and let X start.
> 
> 4. Log in via SSH and run four separate loops, each of which starts a
> set of programs, sleeps for a prime amount of time, kills them and sleep
> for another prime amount of time.  One loop ran five xterms, one ran two
> glxgears (one fullscreen) and one ran twenty xeyes while the final loop
> ran a fulscreen mplayer.  When I have run this kind of load
> interactively it hangs the machine within 20-30 minutes, run via SSH it
> ran stably for over 12 hours.
> 
> Thus I conclude that the thing that triggers the bug is dependent on
> psmouse or (inclusive-or) interactive use of the machine via keyboard
> and mouse.

It's important to make the distinction between these possibilities
though:

Can you still trigger the hang moving the mouse interactively (e.g. with
a USB mouse) when psmouse was never loaded?

If yes, does Option "SWcursor" in xorg.conf work around the problem?
(Verify in Xorg.0.log that the option takes effect)


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