igt@i915_selftest@mock_timelines - incomplete - BUG: kernel NULL pointer dereference

https://intel-gfx-ci.01.org/tree/drm-tip/IGT_5364/shard-skl5/igt@i915_selftest@mock_timelines.html

<7> [91.260675]  mock: [drm:intel_uc_init_early [i915]] enable_guc=0 (guc:no submission:no huc:no)
<1> [91.266904] BUG: kernel NULL pointer dereference, address: 0000000000000220
<1> [91.266984] #PF: supervisor read access in kernel mode
<1> [91.267040] #PF: error_code(0x0000) - not-present page
<6> [91.267094] PGD 0 P4D 0 
<4> [91.267141] Oops: 0000 [#1] PREEMPT SMP PTI
<4> [91.267197] CPU: 2 PID: 1064 Comm: i915_selftest Tainted: G     U            5.5.0-rc5-CI-CI_DRM_7719+ #1
<4> [91.267285] Hardware name: Google Caroline/Caroline, BIOS MrChromebox 08/27/2018
<4> [91.267915] RIP: 0010:active_debug_hint+0x0/0x20 [i915]
<4> [91.267978] Code: 89 83 d8 a3 00 00 31 c0 5b c3 b8 ed ff ff ff 5b c3 66 0f 1f 84 00 00 00 00 00 48 8b bf d8 a3 00 00 e9 14 4c 16 e1 0f 1f 40 00 <48> 8b 87 f8 00 00 00 48 85 c0 74 02 f3 c3 48 8b 87 00 01 00 00 48
<4> [91.268134] RSP: 0018:ffffc900003478f8 EFLAGS: 00010282
<4> [91.268194] RAX: ffffffffa0131b10 RBX: ffffc90000347920 RCX: 0000000000000001
<4> [91.268263] RDX: 0000000000000000 RSI: ffffffff8231a254 RDI: 0000000000000128
<4> [91.268331] RBP: ffffffffa03359e0 R08: ffff888172fa08f8 R09: 0000000000000000
<4> [91.268397] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8231a254
<4> [91.268464] R13: ffffffffa03359e0 R14: ffffffff83ddf248 R15: ffff88816ab09d38
<4> [91.268532] FS:  00007fe22f1fae40(0000) GS:ffff88817ad00000(0000) knlGS:0000000000000000
<4> [91.268622] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4> [91.268686] CR2: 0000000000000220 CR3: 000000016eee0005 CR4: 00000000003606e0
<4> [91.268743] Call Trace:
<4> [91.268795]  debug_print_object+0x34/0x90
<4> [91.268855]  debug_object_assert_init+0x15c/0x180
<4> [91.269361]  ? i915_active_acquire_if_busy+0x10/0x50 [i915]
<4> [91.269919]  i915_active_acquire_if_busy+0x10/0x50 [i915]
<4> [91.270468]  i915_active_acquire+0x10/0xd0 [i915]
<4> [91.270970]  __intel_context_active+0x87/0x310 [i915]
<4> [91.271573]  i915_active_acquire+0x4b/0xd0 [i915]
<4> [91.272081]  __intel_context_do_pin+0x53/0x1d0 [i915]
<4> [91.272585]  create_kernel_context+0x70/0xc0 [i915]
<4> [91.273082]  mock_engine_init+0x3f/0x70 [i915]
<4> [91.273656]  mock_gem_device+0x249/0x340 [i915]
<4> [91.274194]  mock_hwsp_freelist+0x83/0x490 [i915]
<4> [91.274262]  ? ring_buffer_lock_reserve+0x154/0x3f0
<4> [91.274860]  ? __i915_subtests+0x82/0x210 [i915]
<4> [91.274921]  ? trace_vbprintk+0x16a/0x210
<4> [91.274990]  ? __trace_bprintk+0x57/0x80
<4> [91.275583]  ? __i915_subtests+0xb8/0x210 [i915]
<4> [91.276122]  ? __mock_hwsp_record+0x90/0x90 [i915]
<4> [91.276710]  __i915_subtests+0xb8/0x210 [i915]
<4> [91.277305]  ? i915_perf_selftests+0x60/0x60 [i915]
<4> [91.277889]  ? __i915_nop_setup+0x10/0x10 [i915]
<4> [91.278489]  __run_selftests+0x134/0x170 [i915]
<4> [91.278551]  ? 0xffffffffa05f1000
<4> [91.279127]  i915_mock_selftests+0x27/0x50 [i915]
<4> [91.279606]  i915_init+0x12/0x7c [i915]
<4> [91.279662]  ? 0xffffffffa05f1000
<4> [91.279710]  do_one_initcall+0x58/0x300
<4> [91.279770]  ? rcu_read_lock_sched_held+0x4d/0x80
<4> [91.279832]  ? kmem_cache_alloc_trace+0x290/0x2c0
<4> [91.279904]  do_init_module+0x56/0x1f2
<4> [91.279981]  load_module+0x243e/0x29f0
<4> [91.280101]  ? __do_sys_finit_module+0xe9/0x110
<4> [91.280167]  __do_sys_finit_module+0xe9/0x110
<4> [91.280256]  do_syscall_64+0x4f/0x220
<4> [91.280313]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4> [91.280371] RIP: 0033:0x7fe22e8a7839
<4> [91.280422] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 1f f6 2c 00 f7 d8 64 89 01 48
<4> [91.280561] RSP: 002b:00007fff2a1bb938 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
<4> [91.280623] RAX: ffffffffffffffda RBX: 000055d1af018dd0 RCX: 00007fe22e8a7839
<4> [91.280671] RDX: 0000000000000000 RSI: 000055d1af01ddd0 RDI: 0000000000000006
<4> [91.280719] RBP: 000055d1af01ddd0 R08: 0000000000000004 R09: 000055d1af01e820
<4> [91.280766] R10: 00007fff2a1bba80 R11: 0000000000000246 R12: 0000000000000000
<4> [91.280814] R13: 000055d1af014c00 R14: 0000000000000020 R15: 0000000000000048
<4> [91.280879] Modules linked in: i915(+) snd_hda_codec_hdmi x86_pkg_temp_thermal coretemp snd_intel_dspcfg crct10dif_pclmul snd_hda_codec crc32_pclmul snd_hwdep ghash_clmulni_intel snd_hda_core snd_pcm cdc_ether usbnet btusb r8152 btrtl btbcm mii btintel bluetooth ecdh_generic ecc i2c_hid pinctrl_sunrisepoint pinctrl_intel prime_numbers intel_lpss_pci [last unloaded: i915]
<4> [91.281119] CR2: 0000000000000220
<4> [91.281154] ---[ end trace ad55a2cd742c2fde ]---