Comment 15 for bug 429241

@Chris -- will get that information too next time round...

It has also been suggested that the patch below might be pertinent (from drm-intel). Can you tell if we might have a split command from the GPU dumps?

commit 0ef82af7253c1929a3995f271b8b0db462d1a0c3
Author: Chris Wilson <email address hidden>
Date: Sat Sep 5 18:07:06 2009 +0100

    drm/i915: Pad ringbuffer with NOOPs before wrapping

    According to the docs, the ringbuffer is not allowed to wrap in the middle
    of an instruction.

    G45 PRM, Vol 1b, p101:
      While the “free space” wrap may allow commands to be wrapped around the
      end of the Ring Buffer, the wrap should only occur between commands.
      Padding (with NOP) may be required to follow this restriction.

    Do as commanded.

    [Having seen bug reports where there is evidence of split commands, but
    apparently the GPU has continued on merrily before a bizarre and untimely
    death, this may or may not fix a few random hangs.]