[..]
[ 1687.613507] [drm:i915_hangcheck_hung] *ERROR* Hangcheck timer elapsed... GPU hung
[ 1687.613517] [drm] capturing error event; look for more information in /debug/dri/0/i915_error_state
[ 1687.622968] [drm] Enabling RC6 states: RC6 on, RC6p off, RC6pp off