[Intel-gfx] [PATCH 02/17] drm/i915/ringbuffer: Brute force context restore

[Joonas Lahtinen]

Quoting Chris Wilson (2018-06-10 22:43:10)
> An issue encountered with switching mm on gen7 is that the GPU likes to
> hang (with the VS unit busy) when told to force restore the current
> context. We can simply workaround this by substituting the
> MI_FORCE_RESTORE flag with a round-trip through the kernel_context,
> forcing the context to be saved and restored; thereby reloading the
> PP_DIR registers and updating the modified page directory!
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> Cc: Matthew Auld <matthew.william.auld at gmail.com>

Commit message checks out with code, and as you obviously have it
crunching through the testsuites, must be the right thing to do.

Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

Regards, Joonas