[   19.972658] vboxdrv: Found 8 processor cores.
[   19.975095] vboxdrv: fAsync=0 offMin=0x165 offMax=0x7760
[   19.975179] vboxdrv: TSC mode is 'synchronous', kernel timer mode is 'normal'.
[   19.975181] vboxdrv: Successfully loaded version 4.3.2_Ubuntu (interface 0x001a0005).
[   20.013649] vboxpci: IOMMU not found (not registered)
[   20.129800] init: plymouth-stop pre-start process (1688) terminated with status 1
[ 2646.699697] perf samples too long (2531 > 2500), lowering kernel.perf_event_max_sample_rate to 50000
[ 5600.428474] perf samples too long (5007 > 5000), lowering kernel.perf_event_max_sample_rate to 25000
[21594.054753] [drm] stuck on render ring
[21594.054757] [drm] stuck on blitter ring
[21594.054760] [drm] GPU crash dump saved to /sys/class/drm/card0/error
[21594.054762] [drm] GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.
[21594.054763] [drm] Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel
[21594.054764] [drm] drm/i915 developers can then reassign to the right component if it's not a kernel issue.
[21594.054766] [drm] The gpu crash dump is required to analyze gpu hangs, so please always attach it.