9141 Aug 16 23:58:00 wolf kernel: [ 997.556884] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 9142 Aug 16 23:58:00 wolf kernel: [ 997.556940] IP: drm_dp_get_mst_branch_device+0x58/0xe0 [drm_kms_helper] 9143 Aug 16 23:58:00 wolf kernel: [ 997.556957] PGD 0 9144 Aug 16 23:58:00 wolf kernel: [ 997.556957] P4D 0 9145 Aug 16 23:58:00 wolf kernel: [ 997.556963] 9146 Aug 16 23:58:00 wolf kernel: [ 997.556975] Oops: 0000 [#1] SMP 9147 Aug 16 23:58:00 wolf kernel: [ 997.556984] Modules linked in: cmac algif_hash rfcomm md4 nls_utf8 cifs ccm fscache xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack libcr 9148 Aug 16 23:58:00 wolf kernel: [ 997.557162] thinkpad_acpi snd_seq_midi ecdh_generic snd_seq_midi_event nvram snd_hda_intel cfg80211 rtsx_pci_ms snd_hda_codec lpc_ich memstick snd_hda_core snd_rawmidi snd_hwdep mei_me snd_pcm snd_seq mei shpchp ie31200_edac snd_seq_device snd 9149 Aug 16 23:58:00 wolf kernel: [ 997.557329] CPU: 1 PID: 230 Comm: kworker/u16:5 Not tainted 4.12.4-041204-generic #201707271932 9150 Aug 16 23:58:00 wolf kernel: [ 997.557350] Hardware name: LENOVO 20AWS37C00/20AWS37C00, BIOS GLET83WW (2.37 ) 03/31/2016 9151 Aug 16 23:58:00 wolf kernel: [ 997.557394] Workqueue: i915-dp i915_digport_work_func [i915] 9152 Aug 16 23:58:00 wolf kernel: [ 997.557409] task: ffff8acae24dda00 task.stack: ffffaa31821d8000 9153 Aug 16 23:58:00 wolf kernel: [ 997.557426] RIP: 0010:drm_dp_get_mst_branch_device+0x58/0xe0 [drm_kms_helper] 9154 Aug 16 23:58:00 wolf kernel: [ 997.557444] RSP: 0018:ffffaa31821dbcc0 EFLAGS: 00010202 9155 Aug 16 23:58:00 wolf kernel: [ 997.557457] RAX: 0000000000000000 RBX: ffff8acaeb4489a0 RCX: 0000000000000004 9156 Aug 16 23:58:00 wolf kernel: [ 997.557474] RDX: ffff8acaeb4489b0 RSI: 0000000000000000 RDI: 0000000000000002 9157 Aug 16 23:58:00 wolf kernel: [ 997.557492] RBP: ffffaa31821dbce0 R08: 0000000000000018 R09: 0000000000000002 9158 Aug 16 23:58:00 wolf kernel: [ 997.557509] R10: ffffaa31821dbc98 R11: 000000010002a96d R12: 0000000000000000 9159 Aug 16 23:58:00 wolf kernel: [ 997.557526] R13: ffff8acaeb448848 R14: 0000000000000003 R15: ffff8acaeb448100 9160 Aug 16 23:58:00 wolf kernel: [ 997.557544] FS: 0000000000000000(0000) GS:ffff8acafe240000(0000) knlGS:0000000000000000 9161 Aug 16 23:58:00 wolf kernel: [ 997.557563] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 9162 Aug 16 23:58:00 wolf kernel: [ 997.557577] CR2: 0000000000000018 CR3: 0000000135c09000 CR4: 00000000001406e0 9163 Aug 16 23:58:00 wolf kernel: [ 997.557595] Call Trace: 9164 Aug 16 23:58:00 wolf kernel: [ 997.557606] drm_dp_mst_hpd_irq+0xd5/0x8a0 [drm_kms_helper] 9165 Aug 16 23:58:00 wolf kernel: [ 997.557635] intel_dp_check_mst_status+0x127/0x1f0 [i915] 9166 Aug 16 23:58:00 wolf kernel: [ 997.557661] ? intel_dp_check_mst_status+0x127/0x1f0 [i915] 9167 Aug 16 23:58:00 wolf kernel: [ 997.557687] intel_dp_hpd_pulse+0x19f/0x310 [i915] 9168 Aug 16 23:58:00 wolf kernel: [ 997.557712] i915_digport_work_func+0x95/0x110 [i915] 9169 Aug 16 23:58:00 wolf kernel: [ 997.557730] process_one_work+0x1e9/0x410 9170 Aug 16 23:58:00 wolf kernel: [ 997.557743] worker_thread+0x4b/0x410 9171 Aug 16 23:58:00 wolf kernel: [ 997.557755] kthread+0x109/0x140 9172 Aug 16 23:58:00 wolf kernel: [ 997.557766] ? process_one_work+0x410/0x410 9173 Aug 16 23:58:00 wolf kernel: [ 997.557780] ? kthread_create_on_node+0x70/0x70 9174 Aug 16 23:58:00 wolf kernel: [ 997.557794] ? kthread_create_on_node+0x70/0x70 9175 Aug 16 23:58:00 wolf kernel: [ 997.557809] ret_from_fork+0x25/0x30 9176 Aug 16 23:58:00 wolf kernel: [ 997.557820] Code: 8d 4e ff 4d 8b a4 24 e0 02 00 00 45 85 c9 7e 60 31 c0 b9 04 00 00 00 89 c6 4d 8d 44 24 18 d1 fe 48 63 f6 41 0f b6 7c 35 00 d3 ff <49> 8b 4c 24 18 83 e7 0f 49 39 c8 48 8d 71 f0 75 0f eb 1e 48 8b 9177 Aug 16 23:58:00 wolf kernel: [ 997.557889] RIP: drm_dp_get_mst_branch_device+0x58/0xe0 [drm_kms_helper] RSP: ffffaa31821dbcc0 9178 Aug 16 23:58:00 wolf kernel: [ 997.557913] CR2: 0000000000000018 9179 Aug 16 23:58:00 wolf kernel: [ 997.570407] ---[ end trace f220a29d90d857d0 ]---