Bug 95165

Using the drm-intel-nightly kernel up to commit 

commit b29d3f4720fd2b385caca40ccd6f95ad9736edd8
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Mon Apr 25 09:36:12 2016 +0200

it crashes on resume, in the following use case:

- I docked the T450s in the UltraDock with two external monitors connected, internal display was turned off, only the external monitors were on.

- The lid was closed, and the notebook suspended.

- The notebook was then undocked and the lid was opened.

- The notebook resumed, but the kernel crashed right away.



The stack trace:

[  123.515566] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[  123.515572] IP: [<ffffffffc015b4a9>] drm_atomic_helper_check_modeset+0x199/0xb10 [drm_kms_helper]
[  123.515573] PGD 0 
[  123.515574] Oops: 0000 [#1] SMP 
[  123.515594] Modules linked in: hid_generic hid_cherry usbhid hid drbg ansi_cprng ctr ccm ip6t_REJECT nf_reject_ipv6 ip6table_filter ip6_tables iptable_nat nf_nat_ipv4 nf_nat xt_tcpudp nf_conntrack_ipv4 nf_defrag_ipv4 ipt_REJECT 
nf_reject_ipv4 xt_conntrack iptable_filter ip_tables x_tables dm_crypt cmac rfcomm bnep arc4 intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul iwlmvm crc32_pclmul ghash_clmulni_intel mac80211 btusb btrtl btbcm iwlwifi btintel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd cdc_mbim joydev input_leds cfg80211 serio_raw cdc_wdm cdc_ncm binfmt_misc usbnet bluetooth mii cdc_acm intel_pch_thermal snd_hda_codec_hdmi rtsx_pci_ms memstick snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core                                                                                                          
[  123.515603]  thinkpad_acpi snd_hwdep lpc_ich snd_pcm nvram shpchp snd_timer mei_me snd soundcore mei parport_pc ppdev nf_conntrack_ftp nf_conntrack lp parport mac_hid rtsx_pci_sdmmc i915 i2c_algo_bit psmouse drm_kms_helper sysco
pyarea sysfillrect rtsx_pci e1000e sysimgblt ahci fb_sys_fops libahci drm ptp pps_core wmi video fjes                                                                                                                                  
[  123.515604] CPU: 0 PID: 178 Comm: kworker/u16:5 Not tainted 4.6.0-rc4+ #1
[  123.515605] Hardware name: LENOVO 20BWS00V00/20BWS00V00, BIOS JBET51WW (1.16 ) 07/08/2015
[  123.515608] Workqueue: events_unbound async_run_entry_fn
[  123.515609] task: ffff88034905c740 ti: ffff8803496a8000 task.ti: ffff8803496a8000
[  123.515613] RIP: 0010:[<ffffffffc015b4a9>]  [<ffffffffc015b4a9>] drm_atomic_helper_check_modeset+0x199/0xb10 [drm_kms_helper]
[  123.515614] RSP: 0018:ffff8803496abad0  EFLAGS: 00010246
[  123.515614] RAX: 0000000000000000 RBX: ffff88034cef2400 RCX: 0000000000000008
[  123.515615] RDX: ffff88031ac9dd40 RSI: ffff88008b9e8d00 RDI: ffff88034cef2400
[  123.515615] RBP: ffff8803496abb20 R08: 0000000000000003 R09: 0000000000072008
[  123.515616] R10: ffff88008b9e8ca0 R11: ffffffffc02c3100 R12: ffff88008b9e8920
[  123.515616] R13: 0000000000000006 R14: ffff88034dda7000 R15: ffff88034dda5800
[  123.515617] FS:  0000000000000000(0000) GS:ffff88035dc00000(0000) knlGS:0000000000000000
[  123.515617] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  123.515618] CR2: 0000000000000008 CR3: 0000000001e06000 CR4: 00000000003406f0
[  123.515618] Stack:
[  123.515620]  ffff8803496abb38 ffff8803496abb30 ffffffff8102c689 0000000000000000
[  123.515621]  0000000000000000 ffff88034cef2400 ffff88034f338000 0000000000000001
[  123.515622]  ffff88034e135300 ffff88034cef2400 ffff8803496abc08 ffffffffc02381d1
[  123.515622] Call Trace:
[  123.515624]  [<ffffffff8102c689>] ? __switch_to+0x1d9/0x510
[  123.515644]  [<ffffffffc02381d1>] intel_atomic_check+0x31/0x21e0 [i915]
[  123.515655]  [<ffffffffc01d5a14>] ? intel_runtime_pm_put+0x64/0xb0 [i915]
[  123.515665]  [<ffffffffc01d5bd9>] ? intel_display_power_put+0xd9/0x140 [i915]
[  123.515677]  [<ffffffffc0063db7>] drm_atomic_check_only+0x137/0x5f0 [drm]
[  123.515687]  [<ffffffffc01d5bd9>] ? intel_display_power_put+0xd9/0x140 [i915]
[  123.515688]  [<ffffffff81421801>] ? pci_pm_thaw+0x41/0x90
[  123.515696]  [<ffffffffc0064287>] drm_atomic_commit+0x17/0x60 [drm]
[  123.515711]  [<ffffffffc0241e28>] intel_display_resume+0xb8/0x140 [i915]
[  123.515712]  [<ffffffff81421850>] ? pci_pm_thaw+0x90/0x90
[  123.515720]  [<ffffffffc01b80e5>] i915_drm_resume+0xe5/0x170 [i915]
[  123.515727]  [<ffffffffc01b8197>] i915_pm_resume+0x27/0x30 [i915]
[  123.515728]  [<ffffffff814218b4>] pci_pm_resume+0x64/0xa0
[  123.515731]  [<ffffffff8153804e>] dpm_run_callback+0x4e/0x130
[  123.515732]  [<ffffffff815385d3>] device_resume+0xd3/0x1f0
[  123.515734]  [<ffffffff8153870d>] async_resume+0x1d/0x50
[  123.515735]  [<ffffffff810a1548>] async_run_entry_fn+0x48/0x150
[  123.515737]  [<ffffffff81098a40>] process_one_work+0x150/0x3f0
[  123.515738]  [<ffffffff810991fb>] worker_thread+0x12b/0x4b0
[  123.515740]  [<ffffffff810990d0>] ? rescuer_thread+0x340/0x340
[  123.515741]  [<ffffffff8109e9e9>] kthread+0xc9/0xe0
[  123.515743]  [<ffffffff817ffd22>] ret_from_fork+0x22/0x40
[  123.515744]  [<ffffffff8109e920>] ? kthread_park+0x60/0x60
[  123.515757] Code: 63 c5 4c 8b 34 c2 48 8b 53 40 4d 85 f6 4c 8b 24 c2 0f 84 ee 00 00 00 f6 05 24 6d f2 ff 10 0f 85 c5 07 00 00 49 8b 86 80 03 00 00 <48> 8b 78 08 49 8b 44 24 08 48 39 c7 74 41 48 85 ff 74 18 4c 8b 
[  123.515761] RIP  [<ffffffffc015b4a9>] drm_atomic_helper_check_modeset+0x199/0xb10 [drm_kms_helper]
[  123.515761]  RSP <ffff8803496abad0>
[  123.515762] CR2: 0000000000000008