[Intel-gfx] GPU-hang on i830

[Chris Wilson]

On Wed, Sep 10, 2014 at 03:25:31PM +0200, Thomas Richter wrote:
> Am 10.09.2014 14:22, schrieb Daniel Vetter:
> >On Wed, Sep 10, 2014 at 02:17:30PM +0200, Thomas Richter wrote:
> >>Hi Daniel, hi Ville,
> >>
> >>just tried the new 3.17.0+rc4 kernel, though with old userspace (i.e.
> >>xserver-xorg-video-intel is *old*, libdrm is old, mesa is old). If I do, I
> >>get a "GPU hung" from xorg.conf. The same userspace works fine on 3.15.0
> >>with patches from Ville.
> >>
> >>Is this expected behavior or should I open up a bug report (I have dmesg
> >>output and debugging output from DRI ready on this, but it's a bith
> >>lengthy.)
> >Please retest with latest drm-intel-nightly, if just merged a patch from
> >Chris to prevent gpu hangs on i830/i845. If it still blows up please
> >attach and error state captured from that kernel.
> No, not merged from a patch. This is a clean checkout of "master".
> drm-intel-nightly did not contain the watermark fixes
> the last time I checked. Error state is attached. I put Chris into CC.

The w/a buffer is missing a good chunk of that dying batch. So seems
related to the issue I had with corruption in the w/a buffer. But you
already have the deadbeef patch, so it is not going to be so easy to
fix. What would also be interesting is determining what triggered the
regression, but that can be pretty painful on those machines.

Does your machine support clflush?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre