igt@i915_selftest@live@hugepages - dmesg-fail - i915/i915_gem_huge_page_live_selftests: igt_ppgtt_sanity_check failed with error

http://gfx-ci.igk.intel.com/cibuglog-ng/testresult/1425287025?query_key=6d41687afc91e9313303649160791c1a2e7369e8

<7> [422.584754] i915 0000:00:02.0: [drm:i915_gem_open [i915]]
<3> [422.588200] n=1 ptr[1]=0, val=8
<3> [422.591800] cpu-check failed at offset=0
<3> [422.595874] igt_ppgtt_sanity_check write-huge failed with size=65536 pages=65536 i=0, j=0
<3> [422.616596] i915/i915_gem_huge_page_live_selftests: igt_ppgtt_sanity_check failed with error -22
<7> [422.625553] i915 0000:00:02.0: [drm:intel_power_well_enable [i915]] enabling PW_2
<7> [422.626077] i915 0000:00:02.0: [drm:intel_power_well_enable [i915]] enabling PW_A
<7> [422.626278] i915 0000:00:02.0: [drm:intel_power_well_enable [i915]] enabling PW_B
<7> [422.626470] i915 0000:00:02.0: [drm:intel_power_well_enable [i915]] enabling PW_C
<7> [422.626676] i915 0000:00:02.0: [drm:intel_power_well_enable [i915]] enabling PW_D
<7> [422.644135] intel_gt_set_wedged called from intel_gt_set_wedged_on_fini+0xd/0x30 [i915]
<7> [422.646208] intel_gt_set_wedged called from intel_gt_set_wedged_on_fini+0xd/0x30 [i915]