[Intel-gfx] ✗ Fi.CI.IGT: failure for series starting with [01/19] drm/i915/execlists: Always clear ring_pause if we do not submit

[Chris Wilson]

Quoting Patchwork (2019-06-24 09:55:07)
> #### Possible regressions ####
> 
>   * igt at gem_ctx_switch@basic-queue-heavy:
>     - shard-skl:          [PASS][1] -> [INCOMPLETE][2]
>    [1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_6331/shard-skl4/igt@gem_ctx_switch@basic-queue-heavy.html
>    [2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_13401/shard-skl6/igt@gem_ctx_switch@basic-queue-heavy.html

Fwiw, this smells like a use-after-free that does not appear before

	drm/i915: Protect request retirement with timeline->mutex

My guess is that I dropped a reference and freed an active request,
though I haven't yet found the hole.
-Chris