[Intel-gfx] [RFC PATCH 2/2] drm/i915: Fix panic if nothing to promote after preempt on reset

[Chris Wilson]

Quoting Janusz Krzysztofik (2019-08-06 13:24:58)
> Execlists state machine always falls through from PREEMPT to PROMOTE,
> expecting pending to be valid.  Apparently it not always happens to be
> the case, at least during reset.  Assuming this unexpected behavior
> depends on hardware, fix the issue by introducing a conditional break.

Nak. Find the reason why the HW is not behaving as is specified.
-Chris