We grab the struct_mutex in intel_crtc_page_flip, but if we are wedged
or a reset is in progress we bail early but never seem to actually
release the lock.
Fixes: 7f1847ebf48b ("drm/i915: Simplify checking of GPU reset_counter in display pageflips") Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Matthew Auld <matthew.auld@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20161128103648.9235-1-matthew.auld@intel.com Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: <stable@vger.kernel.org> # v4.7+
(cherry picked from commit ddbb271aea87fc6004d3c8bcdb0710e980c7ec85) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
(cherry picked from commit e411072d5740a49cdc9d0713798c30440757e451) Signed-off-by: Jani Nikula <jani.nikula@intel.com>