GPU hung with Linux-3.2-rc6

[Daniel Vetter]

On Mon, Jan 2, 2012 at 08:09, Udo Steinberg <udo at hypervisor.org> wrote:
> On Thu, 22 Dec 2011 09:22:33 +0100 Daniel Vetter (DV) wrote:
>
> DV> Can you please apply the patch available at
> DV>
> DV> http://cgit.freedesktop.org/~danvet/drm/patch/?id=0b3ecfa8c9b00f50d514fbcc12e34882b0fa695a
> DV>
> DV> This one will let your gpu keep hanging in the "stuck on semphore wait"
> DV> condition. Later on the hangcheck should kick in and grab a gpu error
> DV> state (in the file i915_error_state in debugfs). Can you please attach
> DV> that one?
>
> Hi,
>
> i915_error_state and dmesg are attached. This was with Linux 3.2.0-rc6 and
> the aforementioned patch applied.

Thanks a lot for gathering the error state. It looks like the
semaphore code deadlocked, which should not have happened. Can you
please test with the my-next branch available at:

http://cgit.freedesktop.org/~danvet/drm/log/?h=my-next

It contains a few fixes for races (that might cause your issue) and
dumps some additional information into the error state. You need to
boot with i915.semaphores=1 because they're not enabled by default in
that tree.

Again, please attach the error state if the gpu hangs.

Yours, Daniel
-- 
Daniel Vetter
daniel.vetter at ffwll.ch - +41 (0) 79 364 57 48 - http://blog.ffwll.ch