Created attachment 83816 [details]
dmesg

System Environment:
--------------------------
Platform:  PNV/ILK/SNB/IVB/HSW
Kernel: (drm-ntel-next-queued)ddfe15677d9c47f2491e401cd773b45e1aac74bf

Bug detailed description:
-----------------------------
It fails on all platforms: PNV/ILK/SNB/IVB/HSW.It happens on drm-intel-nightly, drm-intel-next-queued, drm-intel-fixes kernel.
It's a new igt case.

output:
leaked 177 objects
prime_self_import: prime_self_import.c:341: test_export_close_race: Assertion `obj_count == 0' failed.
Aborted (core dumped)

[   38.315335] Call Trace:
[   38.315360]  [<ffffffff810d5800>] ? filp_close+0x4e/0x68
[   38.315400]  [<ffffffff810d6bac>] ? SyS_close+0x1c/0x3f
[   38.315442]  [<ffffffff816f7ed2>] ? system_call_fastpath+0x16/0x1b
[   38.315485] Code: ef e8 3a ff ff ff 49 8b 1c 24 48 85 db 75 b1 80 45 20 01 5e 5b 5d 41 5c 31 c0 41 5d c3 41 54 49 89 f4 55 48 89 fd 53 48 8b 77 20 <8b> 06 66 25 00 f0 66 3d 00 40 0f 85 a0 00 00 00 48 8b 3d f0 35
[   38.315828] RIP  [<ffffffff811058b1>] dnotify_flush+0xe/0xc3
[   38.315872]  RSP <ffff8801120e7f38>
[   38.315898] CR2: 0000000000000000
[   38.315936] ---[ end trace 678133e1a3f89f18 ]---
[   38.345869] BUG: unable to handle kernel NULL pointer dereference at           (null)
[   38.345926] IP: [<ffffffff811058b1>] dnotify_flush+0xe/0xc3

Reproduce steps:
----------------------------
1. ./prime_self_import --run-subtest export-vs-gem_close-race