Open bug in launchpad.net :
[ 4917.268485] [drm] GPU HANG: ecode 6:-1:0x00000000, reason: Kicking stuck semaphore on render ring, action: continue
[ 4917.268489] [drm] GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.
[ 4917.268491] [drm] Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel
[ 4917.268493] [drm] drm/i915 developers can then reassign to the right component if it's not a kernel issue.
[ 4917.268494] [drm] The gpu crash dump is required to analyze gpu hangs, so please always attach it.
[ 4917.268496] [drm] GPU crash dump saved to /sys/class/drm/card0/error
Thanks for you work,
Report of package libdrm in ubuntu:
*** This bug has been marked as a duplicate of bug 54226 ***