igt@kms_atomic@plane-immutable-zpos - timeout - ffff88817d4c50b0 (&gt->reset.mutex){+.+.}-{3:3}, at: i915_request_wait_timeout

https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_13320/shard-dg2-7/igt@kms_atomic@plane-immutable-zpos.html#dmesg-warnings7831

<4> [852.418563] 3 locks held by igt_runner/930:
<4> [852.418565]  #0: ffff888105621430 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0x64/0xe0
<4> [852.418574]  #1: ffffffff827397c0 (rcu_read_lock){....}-{1:2}, at: __handle_sysrq+0x4/0x270
<4> [852.418582]  #2: ffffffff827397c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x12/0x1d0
<4> [852.418592] 3 locks held by kms_atomic/1815:
<4> [852.418594]  #0: ffff888100a0c430 (sb_writers#15){.+.+}-{0:0}, at: ksys_write+0x64/0xe0
<4> [852.418602]  #1: ffff88810727b7b8 (&attr->mutex){+.+.}-{3:3}, at: simple_attr_write_xsigned.constprop.0+0x47/0x110
<4> [852.418610]  #2: ffff88817d4c50b0 (&gt->reset.mutex){+.+.}-{3:3}, at: i915_request_wait_timeout+0xa0/0x710 [i915]
<4> [852.418764] 
<4> [852.418765] =============================================
<6> [852.418767] Showing busy workqueues and worker pools:
<6> [852.418813] sysrq: Show Memory
<4> [852.418823] Mem-Info:
<4> [852.418825] active_anon:3801 inactive_anon:52599 isolated_anon:0
 active_file:72534 inactive_file:12346 isolated_file:0
 unevictable:4 dirty:405 writeback:0
 slab_reclaimable:11028 slab_unreclaimable:29919
 mapped:15151 shmem:298 pagetables:1175