[Intel-gfx] [PATCH 11/14] drm/i915: Drop the shadow ring state from the error capture

[Chris Wilson]

Quoting Mika Kuoppala (2020-01-09 09:04:31)
> Chris Wilson <chris at chris-wilson.co.uk> writes:
> 
> > The shadow ring regs (ring->head, ring->tail) are meaningless in the
> > post-mortem dump as they do not related to anything on HW. Remove them
> > from the coredump.
> 
> We have been dumping these just to check that our bookkeepping matches?

Kind off, but they never really match since the ring->head is very lazy,
and ring->tail is wherever the user got up to. We have the relevant
information from the request where we expect to be in the ring for the
error, and the HW tells us where it was executing.
-Chris