[Intel-gfx] [PATCH] drm/i915/guc: Prevent ggtt->invalidate assert during GuC reload

[Chris Wilson]

Quoting Michel Thierry (2017-07-26 21:59:07)
> On 6/30/2017 10:41 AM, Michel Thierry wrote:
> > The driver reloads the GuC firmware after full gpu reset or
> > suspend/resume, but it never disables the GuC beforehand.
> > This leads us to hit the assert inside i915_ggtt_enable_guc added
> > by commit 04f7b24eccdf ("drm/i915/guc: Assert that we switch between
> > known ggtt->invalidate functions").
> > 
> 
> Ping...
> I know this isn't important, since who is using guc? (I only know people 
> who hates it).
> 
> Or we just remove the assert in i915_ggtt_enable_guc.

Kind of. This implies we've lost control over the guc-driver state. My
feeling is that we need a post-reset hook for the guc so that we can
throw away the lost state.
-Chris