==System Environment==
--------------------------
Regression: not sure

Non-working platforms: BDW

==kernel==
--------------------------
drm-intel-nightly/6643662c2ad37b156b0bee95a1c28debe191a3ed
drm-intel-next-queued/140fd38dc4962ae3694f81900b51c567df1b6d33
drm-intel-fixes/b0616c5306b342ceca07044dbc4f917d95c4f825

==Bug detailed description==
-----------------------------
Run automation testing, gem_userptr_blits/coherency-sync and gem_userptr_blits/coherency-unsync will be crash.
If clean boot system then run binary, it doesn't have this issue. I guess some case impacts it, I am not sure which one.
I test it on BDW with drm-intel-nightly, drm-intel-next-queued and drm-intel-fixes kernel.

Run binary output:
[root@x-bdw01 tests]# time ./gem_userptr_blits --run-subtest coherency-sync
IGT-Version: 1.9-g6262f35 (x86_64) (Linux: 3.18.0_drm-intel-nightly_664366_20141218+ x86_64)
Aperture size is 4096 MiB
Total RAM is 3864 MiB
Testing unsynchronized mappings...
Testing synchronized mappings...
Using 2x2730 1MiB buffers
Verifying initialisation...
Cyclic blits cpu->gpu, forward...
Cyclic blits gpu->cpu, backward...
Random blits...
Subtest coherency-sync: SUCCESS (324.783s)

real    5m24.835s
user    0m8.883s
sys     0m45.254s

test log:
@test: Intel_gpu_tools/igt_gem_userptr_blits_coherency-sync
info: @@@Returncode: 0

test case start at: Thu Dec 11 17:21:54 2014
test case end at:   Thu Dec 11 17:22:12 2014

Errors:


Dmesg:
<4>[  234.600396] CPU: 0 PID: 4811 Comm: sshd Not tainted 3.18.0_drm-intel-nightly_34d267_20141210+ #2456


Output:
             command   pid dev master a   uid      magic
Test Environment check: Succeeded.
[1/1] crash: 1 |
[1/1] crash: 1 /


Thank you for running Piglit!
Results have been written to /GFX/Test/Piglit/piglit/t
{
    "results_version": 2,
    "uname": "Linux x-bdw05 3.18.0_drm-intel-nightly_34d267_20141210+ #2456 SMP Wed Dec 10 11:24:26 CST 2014 x86_64 x86_64 x86_64 GNU/Linux\n",
    "time_elapsed": 14.77588415145874,
    "tests": {
        "igt/gem_userptr_blits/coherency-sync": {
            "returncode": -9,
            "err": "",
            "environment": "PIGLIT_SOURCE_DIR=\"/GFX/Test/Piglit/piglit\" PIGLIT_PLATFORM=\"mixed_glx_egl\"",
            "command": "/GFX/Test/Intel_gpu_tools/intel-gpu-tools/tests/gem_userptr_blits --run-subtest coherency-sync",
            "result": "crash",
            "time": 14.573117017745972,
            "out": "IGT-Version: 1.8-gb6f68c1 (x86_64) (Linux: 3.18.0_drm-intel-nightly_34d267_20141210+ x86_64)\nAperture size is 4096 MiB\nTotal RAM is 3874 MiB\nTesting unsynchronized mappings...\n"
        }
    },
    "name": "t",
    "lspci": "00:00.0 Host bridge: Intel Corporation Broadwell-U Host Bridge -OPI (rev 09)\n00:02.0 VGA compatible controller: Intel Corporation Broadwell-U Integrated Graphics (rev 09)\n00:03.0 Audio device: Intel Corporation Broadwell-U Audio Controller (rev 09)\n00:14.0 USB controller: Intel Corporation Wildcat Point-LP USB xHCI Controller (rev 03)\n00:16.0 Communication controller: Intel Corporation Wildcat Point-LP MEI Controller #1 (rev 03)\n00:19.0 Ethernet controller: Intel Corporation Ethernet Connection (3) I218-LM (rev 03)\n00:1f.0 ISA bridge: Intel Corporation Wildcat Point-LP LPC Controller (rev 03)\n00:1f.2 SATA controller: Intel Corporation Wildcat Point-LP SATA Controller [AHCI Mode] (rev 03)\n00:1f.3 SMBus: Intel Corporation Wildcat Point-LP SMBus Controller (rev 03)\n00:1f.6 Signal processing controller: Intel Corporation Wildcat Point-LP Thermal Management Controller (rev 03)\n",
    "options": {
        "profile": [
            "tests/igt.py"
        ],
        "dmesg": false,
        "execute": true,
        "log_level": "quiet",
        "concurrent": "some",
        "valgrind": false,
        "sync": false,
        "filter": [
            "igt/gem_userptr_blits/coherency-sync$"
        ],
        "platform": "mixed_glx_egl",
        "exclude_tests": [],
        "env": {
            "PIGLIT_SOURCE_DIR": "/GFX/Test/Piglit/piglit",
            "PIGLIT_PLATFORM": "mixed_glx_egl"
        },
        "exclude_filter": []
    }
}
returncode: 0
summary: Intel_gpu_tools/igt_gem_userptr_blits_coherency-sync    CRASH   

==Reproduce steps==
---------------------------- 
1. run full igt