System hangs when hot-plugging dual monitor dock

[Bernie Bernstein]

When plugging in my Cable Matters USB-C Dual 4K DisplayPort Docking Station into my system, after it has already booted, the system hangs with a kernel OOPS. This is always repeatable.

Steps to reproduce:

1. Ensure docking station is unplugged or shut-off.
2. Boot up computer.
3. Turn-on docking station and plug into to system.

If the docking station is plugged in before the system boots, it works fine. It can even be unpluged and hot-plugged without issue at that point.

This kernel Oops occurs when the system hangs:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000320
PGD 0 P4D 0
SMP NOPTI
CPU: 3 PID: 84 Comm: kworker/3:1 Tainted: G D OE 4.18.0-16-generic #17-Ubuntu
Hardware name: HP HP EliteBook 755 G5/83D5, BIOS Q81 Ver. 01.04.01 09/13/2018
Workqueue: events_long drm_dp_mst_link_probe_work [drm_kms_helper]
RIP: 0010:mutex_lock+0x1d/0x30
Code: 5d c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 8e df ff ff 31 c0 65 48 8b 14 25 00 5c 01 00 <f0> 48 0f b1 13 74 08 48 89 df e8 b4 ff ff ff 5b 5d c3 90 0f 1f 44
RSP: 0018:ffffb6c0c1efbd78 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000320 RCX: ffff8ed7cfb5c800
RDX: ffff8ed7d3830000 RSI: 0000000000000202 RDI: 0000000000000320
RBP: ffffb6c0c1efbd80 R08: 0000000000000201 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8ed7df6e1ac8 R12: 0000000000000000
R13: ffff8ed7cfb5c468 R14: ffff8ed7d3b33f60 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8ed7df6c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000320 CR3: 00000003b5d6e000 CR4: 00000000003406a0
Call Trace:
 drm_dp_mst_wait_tx_reply+0x155/0x1f0 [drm_kms_helper]
 ? wait_woken+0x80/0x80
 drm_dp_send_enum_path_resources.isra.24+0x69/0xf0 [drm_kms_helper]
 drm_dp_check_and_send_link_address+0xa1/0xd0 [drm_kms_helper]
 drm_dp_mst_link_probe_work+0x4f/0x80 [drm_kms_helper]
 process_one_work+0x20f/0x410
 worker_thread+0x34/0x400
 kthread+0x120/0x140
 ? pwq_unbound_release_workfn+0xd0/0xd0
 ? kthread_bind+0x40/0x40
 ret_from_fork+0x22/0x40
Modules linked in: snd_usb_audio snd_usbmidi_lib usbhid cdc_ether uas usbnet usb_storage r8152 rfcomm binfmt_misc ccm cmac bnep btusb btrtl btbcm btintel bluetooth ecdh_generic uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common videodev media evdi(OE) nfc arc4 joydev nls_iso8859_1 snd_hda_codec_conexant snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel snd_hda_codec edac_mce_amd snd_hda_core snd_hwdep kvm_amd ccp kvm irqbypass snd_pcm crct10dif_pclmul iwlmvm crc32_pclmul ghash_clmulni_intel pcbc snd_seq_midi snd_seq_midi_event mac80211 snd_rawmidi snd_seq snd_seq_device snd_timer iwlwifi aesni_intel snd hp_wmi aes_x86_64 crypto_simd cryptd input_leds glue_helper wmi_bmof serio_raw sparse_keymap hid_multitouch k10temp soundcore cfg80211 ipmi_devintf ipmi_msghandler
 ucsi_acpi typec_ucsi typec mac_hid hp_wireless sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 hid_generic amdkfd amd_iommu_v2 amdgpu chash gpu_sched i2c_algo_bit ttm nvme drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops psmouse drm ahci libahci r8169 nvme_core i2c_piix4 mii i2c_hid wmi hid video
CR2: 0000000000000320
---[ end trace 3aa69f7fb354f0c1 ]---
BUG: unable to handle kernel NULL pointer dereference at 0000000000000320
PGD 0 P4D 0
RIP: 0010:queue_work_on+0x1b/0x40
Code:
SMP NOPTI
CPU: 0 PID: 974 Comm: Xorg Tainted: G D OE 4.18.0-16-generic #17-Ubuntu
Hardware name: HP HP EliteBook 755 G5/83D5, BIOS Q81 Ver. 01.04.01 09/13/2018
RIP: 0010:mutex_lock+0x1d/0x30
Code: 5d c3
58
66 66 2e 0f
01 01 e8 69
1f 84 00
27 fe ff
00
0f 0b e9
00
b5 fc ff
00
ff 0f 1f
00
44 00 00
0f
55 48 89 e5
1f 44 00
53
00 55 48
9c
89 e5 53
58 0f 1f
48
44 00 00 48
89 fb e8
89 c3 fa
8e
66 0f 1f
df
44 00 00 <f0>
ff
48 0f ba 2a
ff 31 c0
00
65 48 8b
73 11 31 c9
14 25 00
48 89 df 57
5c 01 00
9d 0f 1f
<f0>
44 00 00 89
48 0f b1
c8
RSP: 0018:ffffb6c0c2063c98 EFLAGS: 00010002
13
RAX: 0000000000000202 RBX: 0000000000000202 RCX: 0000000000000000
74 08 48 89
RDX: 00000000000003a8 RSI: ffff8ed7df019000 RDI: 0000000000002000
df e8 b4
RBP: ffffb6c0c2063ca0 R08: 0000000000027080 R09: ffffffffa25d9e13
R10: fffffa628ed74840 R11: 0000000000000036 R12: ffff8ed7cfb5c5e6
R13: ffff8ed7801fa800 R14: 0000000000000001 R15: ffff8ed7d3b33f60
FS: 0000000000000000(0000) GS:ffff8ed7df6c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000320 CR3: 00000003b5d6e000 CR4: 00000000003406a0
ff ff ff 5b 5d c3 90 0f 1f 44
RSP: 0018:ffffb6c0c2b3b858 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000320 RCX: ffff8ed7cfb5c800
RDX: ffff8ed7da888000 RSI: 0000000000000206 RDI: 0000000000000320
RBP: ffffb6c0c2b3b860 R08: 0000000000000206 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8ed7df621ac8 R12: 0000000000000000
R13: ffff8ed7cfb5c468 R14: ffff8ed7d3b33f60 R15: 0000000000000000
FS: 00007f9cc3b65a80(0000) GS:ffff8ed7df600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000320 CR3: 000000041a814000 CR4: 00000000003406b0
Call Trace:
 drm_dp_mst_wait_tx_reply+0x155/0x1f0 [drm_kms_helper]
 ? wait_woken+0x80/0x80
 drm_dp_mst_i2c_xfer+0x1b8/0x270 [drm_kms_helper]
 __i2c_transfer+0x119/0x410
 ? _cond_resched+0x19/0x30
 i2c_transfer+0x5a/0xd0
 drm_do_probe_ddc_edid+0xbe/0x140 [drm]
 drm_get_edid+0x51/0x390 [drm]
 ? _cond_resched+0x19/0x30
 drm_dp_mst_get_edid+0x6f/0x90 [drm_kms_helper]
 dm_dp_mst_get_modes+0x8a/0x140 [amdgpu]
 ? drm_helper_probe_detect+0x78/0xa0 [drm_kms_helper]
 drm_helper_probe_single_connector_modes+0x18b/0x700 [drm_kms_helper]
 drm_mode_getconnector+0x40e/0x440 [drm]
 ? drm_mode_connector_property_set_ioctl+0x60/0x60 [drm]
 drm_ioctl_kernel+0xa4/0xf0 [drm]
 drm_ioctl+0x227/0x400 [drm]
 ? drm_mode_connector_property_set_ioctl+0x60/0x60 [drm]
 amdgpu_drm_ioctl+0x4f/0x90 [amdgpu]
 do_vfs_ioctl+0xa8/0x620
 ksys_ioctl+0x67/0x90
 __x64_sys_ioctl+0x1a/0x20
 do_syscall_64+0x5a/0x110
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f9cc4e9c3c7
Code: 00 00 90 48 8b 05 c9 3a 0d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 99 3a 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffecec1ff28 EFLAGS: 00003246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00005601df01d790 RCX: 00007f9cc4e9c3c7
RDX: 00007ffecec1ff60 RSI: 00000000c05064a7 RDI: 000000000000000d
RBP: 00007ffecec1ff60 R08: 00005601df01b0a0 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000003246 R12: 00000000c05064a7
R13: 000000000000000d R14: 000000000000000d R15: 00007ffecec1ff60
Modules linked in: snd_usb_audio snd_usbmidi_lib usbhid cdc_ether uas usbnet usb_storage r8152 rfcomm binfmt_misc ccm cmac bnep btusb btrtl btbcm btintel bluetooth ecdh_generic uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common videodev media evdi(OE) nfc arc4 joydev nls_iso8859_1 snd_hda_codec_conexant snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel snd_hda_codec edac_mce_amd snd_hda_core snd_hwdep kvm_amd ccp kvm irqbypass snd_pcm crct10dif_pclmul iwlmvm crc32_pclmul ghash_clmulni_intel pcbc snd_seq_midi snd_seq_midi_event mac80211 snd_rawmidi snd_seq snd_seq_device snd_timer iwlwifi aesni_intel snd hp_wmi aes_x86_64 crypto_simd cryptd input_leds glue_helper wmi_bmof serio_raw sparse_keymap hid_multitouch k10temp soundcore cfg80211 ipmi_devintf ipmi_msghandler
 ucsi_acpi typec_ucsi typec mac_hid hp_wireless sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 hid_generic amdkfd amd_iommu_v2 amdgpu chash gpu_sched i2c_algo_bit ttm nvme drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops psmouse drm ahci libahci r8169 nvme_core i2c_piix4 mii i2c_hid wmi hid video
CR2: 0000000000000320
---[ end trace 3aa69f7fb354f0c2 ]---
RIP: 0010:queue_work_on+0x1b/0x40
Code: 58 01 01 e8 69 27 fe ff 0f 0b e9 b5 fc ff ff 0f 1f 44 00 00 55 48 89 e5 53 9c 58 0f 1f 44 00 00 48 89 c3 fa 66 0f 1f 44 00 00 <f0> 48 0f ba 2a 00 73 11 31 c9 48 89 df 57 9d 0f 1f 44 00 00 89 c8
RSP: 0018:ffffb6c0c2063c98 EFLAGS: 00010002
RAX: 0000000000000202 RBX: 0000000000000202 RCX: 0000000000000000
RDX: 00000000000003a8 RSI: ffff8ed7df019000 RDI: 0000000000002000
RBP: ffffb6c0c2063ca0 R08: 0000000000027080 R09: ffffffffa25d9e13
R10: fffffa628ed74840 R11: 0000000000000036 R12: ffff8ed7cfb5c5e6
R13: ffff8ed7801fa800 R14: 0000000000000001 R15: ffff8ed7d3b33f60
FS: 00007f9cc3b65a80(0000) GS:ffff8ed7df600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000320 CR3: 000000041a814000 CR4: 00000000003406b0

This issue appears to be related to bug 107738, found upstream in the drm kernel module (https://bugs.freedesktop.org/show_bug.cgi?id=107738). However, the fix for that bug appears to have already been committed downstream, however this bug is still occurring for me.

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: linux-image-4.18.0-16-generic 4.18.0-16.17
ProcVersionSignature: Ubuntu 4.18.0-16.17-generic 4.18.20
Uname: Linux 4.18.0-16-generic x86_64
ApportVersion: 2.20.10-0ubuntu13
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: bernie 2029 F.... pulseaudio
 /dev/snd/controlC1: bernie 2029 F.... pulseaudio
 /dev/snd/controlC0: bernie 2029 F.... pulseaudio
CurrentDesktop: KDE
Date: Wed Mar 13 10:21:30 2019
InstallationDate: Installed on 2019-03-10 (3 days ago)
InstallationMedia: Kubuntu 18.10 "Cosmic Cuttlefish" - Release amd64 (20181017.2)
MachineType: HP HP EliteBook 755 G5
ProcFB: 0 amdgpudrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-16-generic root=UUID=b1aeec1e-bc30-4b40-a818-f9bf0e603915 ro mce=off iommu=soft quiet splash vt.handoff=1
RelatedPackageVersions:
 linux-restricted-modules-4.18.0-16-generic N/A
 linux-backports-modules-4.18.0-16-generic N/A
 linux-firmware 1.175
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 09/13/2018
dmi.bios.vendor: HP
dmi.bios.version: Q81 Ver. 01.04.01
dmi.board.name: 83D5
dmi.board.vendor: HP
dmi.board.version: KBC Version 08.47.00
dmi.chassis.asset.tag: 5CG9082GFP
dmi.chassis.type: 10
dmi.chassis.vendor: HP
dmi.modalias: dmi:bvnHP:bvrQ81Ver.01.04.01:bd09/13/2018:svnHP:pnHPEliteBook755G5:pvr:rvnHP:rn83D5:rvrKBCVersion08.47.00:cvnHP:ct10:cvr:
dmi.product.family: 103C_5336AN HP EliteBook
dmi.product.name: HP EliteBook 755 G5
dmi.product.sku: 4HZ53UT#ABA
dmi.sys.vendor: HP

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[Kai-Heng Feng (kaihengfeng)]

Would it be possible to try kernel < 4.18.0-16?

[Bernie Bernstein (bernie9998)]

I have verified this issue still exists in kernel version 4.18.0-10.

[Kai-Heng Feng (kaihengfeng)]

Similar to LP: #1820811?

[Bernie Bernstein (bernie9998)]

It's possible, though it's hard to confirm as I cannot find a kernel OOPS message in that ticket.

If they can avoid hanging if the dock is plugged in when first booting, then I think they are very likely related.

[Bernie Bernstein (bernie9998)]

I don't think this issue is related to LP #1820811.

In #1820811, the hang always occurs when hot-plugging.

With this issue, if the device is cold plugged (plugged in at boot), it can be disconencted and re-connected without issue.

[Kai-Heng Feng (kaihengfeng)]

Would it be possible for you to test the latest upstream kernel? Refer
to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest
v5.1-rc3 kernel [0].

If this bug is fixed in the mainline kernel, please add the following
tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag:
'kernel-bug-exists-upstream'.

Once testing of the upstream kernel is complete, please mark this bug as
"Confirmed”, and attach dmesg.

Thanks in advance.

[0] https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.1-rc3/

[Kai-Heng Feng (kaihengfeng)]

My bad, didn't notice it's AMD graphics instead of Intel graphics. Please test mainline kernel.

[Bernie Bernstein (bernie9998)]

Issue still remains with the mainline kernel. The contents of the kernel Oops message differs slightly, but still very similar:

[ 27.532858] BUG: unable to handle kernel NULL pointer dereference at 00000000000003e8
[ 27.532862] #PF error: [WRITE]
[ 27.532865] PGD 0 P4D 0
[ 27.532869] Oops: 0002 [#1] SMP NOPTI
[ 27.532873] CPU: 3 PID: 82 Comm: kworker/3:1 Not tainted 5.1.0-050100rc3-generic #201904010618
[ 27.532875] Hardware name: HP HP EliteBook 755 G5/83D5, BIOS Q81 Ver. 01.04.01 09/13/2018
[ 27.532982] Workqueue: events dm_irq_work_func [amdgpu]
[ 27.532989] RIP: 0010:queue_work_on+0x1b/0x40
[ 27.532992] Code: 75 01 01 e8 f9 13 fe ff 0f 0b e9 b5 fc ff ff 0f 1f 44 00 00 55 48 89 e5 53 9c 58 0f 1f 44 00 00 48 89 c3 fa 66 0f 1f 44 00 00 <f0> 48 0f ba 2a 00 73 11 31 c9 48 89 df 57 9d 0f 1f 44 00 00 89 c8
[ 27.532994] RSP: 0018:ffffc16bc1eebc88 EFLAGS: 00010002
[ 27.532996] RAX: 0000000000000202 RBX: 0000000000000202 RCX: 0000000000000001
[ 27.532998] RDX: 00000000000003e8 RSI: ffff9dde1e80d200 RDI: 0000000000002000
[ 27.533000] RBP: ffffc16bc1eebc90 R08: 0000000000027080 R09: ffffffffb8210b0b
[ 27.533002] R10: fffffc35106d5500 R11: ffff9dde1e86ca90 R12: ffff9dde0f2db646
[ 27.533003] R13: ffff9dde1b4b9a80 R14: ffff9dde195eb000 R15: 0000000000000000
[ 27.533006] FS: 0000000000000000(0000) GS:ffff9dde1ecc0000(0000) knlGS:0000000000000000
[ 27.533008] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 27.533010] CR2: 00000000000003e8 CR3: 0000000411ca6000 CR4: 00000000003406a0
[ 27.533011] Call Trace:
[ 27.533026] drm_dp_mst_handle_up_req+0x503/0x550 [drm_kms_helper]
[ 27.533037] drm_dp_mst_hpd_irq+0xbe/0xaa0 [drm_kms_helper]
[ 27.533045] ? drm_dp_mst_hpd_irq+0xbe/0xaa0 [drm_kms_helper]
[ 27.533133] handle_hpd_rx_irq+0x22c/0x2e0 [amdgpu]
[ 27.533219] ? handle_hpd_rx_irq+0x22c/0x2e0 [amdgpu]
[ 27.533306] dm_irq_work_func+0x53/0x70 [amdgpu]
[ 27.533309] process_one_work+0x20f/0x410
[ 27.533312] worker_thread+0x34/0x400
[ 27.533315] kthread+0x120/0x140
[ 27.533318] ? process_one_work+0x410/0x410
[ 27.533320] ? __kthread_parkme+0x70/0x70
[ 27.533325] ret_from_fork+0x22/0x40
[ 27.533327] Modules linked in: cmac bnep btusb btrtl btbcm btintel bluetooth ecdh_generic bonding uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common videodev media nfc edac_mce_amd kvm_amd ccp kvm arc4 irqbypass nls_iso8859_1 crct10dif_pclmul crc32_pclmul snd_hda_codec_conexant ghash_clmulni_intel snd_hda_codec_generic snd_hda_codec_hdmi ledtrig_audio snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_pcm aesni_intel iwlmvm snd_seq_midi snd_seq_midi_event aes_x86_64 crypto_simd mac80211 cryptd snd_rawmidi glue_helper snd_seq iwlwifi snd_seq_device joydev snd_timer input_leds hp_wmi serio_raw sparse_keymap wmi_bmof snd k10temp cfg80211 soundcore ipmi_devintf ipmi_msghandler ucsi_acpi typec_ucsi typec hp_wireless mac_hid sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 amdgpu chash gpu_sched amd_iommu_v2 i2c_algo_bit ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops nvme psmouse ahci drm libahci i2c_piix4 r8169 nvme_core realtek
[ 27.533372...

[Kai-Heng Feng (kaihengfeng)]

Please test 20.04.

[Bernie Bernstein (bernie9998)]

It had actually been working fine in 20.04 until a recent kernel update to 5.4.0-33.37.

Since the update, it always fails with this stack trace:

[140594.217061] ------------[ cut here ]------------
[140594.217062] sysfs group 'power' not found for kobject 'i2c-11'
[140594.217079] WARNING: CPU: 5 PID: 64631 at fs/sysfs/group.c:279 sysfs_remove_group+0x7c/0x80
[140594.217080] Modules linked in: vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) binfmt_misc ccm rfcomm cmac algif_hash algif_skcipher af_alg cdc_ether usbnet r8152 mii snd_usb_audio snd_usbmidi_lib bnep bonding btusb btrtl btbcm btintel bluetooth ecdh_generic ecc evdi(OE) aufs uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common overlay nls_iso8859_1 snd_hda_codec_conexant snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer snd iwlmvm edac_mce_amd mac80211 kvm_amd ccp soundcore libarc4 kvm iwlwifi input_leds joydev serio_raw hp_wmi sparse_keymap ipmi_devintf wmi_bmof hid_multitouch k10temp cfg80211 ipmi_msghandler ucsi_acpi typec_ucsi typec hp_wireless mac_hid sch_fq_codel v4l2loopback(OE) videodev mc parport_pc ppdev lp parport ip_tables x_tables autofs4 uas usb_storage raid10 raid456 async_raid6_recov async_memcpy
[140594.217138] async_pq async_xor async_tx xor usbhid raid6_pq libcrc32c raid1 raid0 multipath linear crct10dif_pclmul crc32_pclmul hid_generic ghash_clmulni_intel amdgpu amd_iommu_v2 gpu_sched i2c_algo_bit ttm nvme aesni_intel drm_kms_helper syscopyarea sysfillrect crypto_simd sysimgblt i2c_hid fb_sys_fops hid ahci psmouse drm cryptd libahci i2c_piix4 glue_helper nvme_core r8169 realtek wmi video i2c_amd_mp2_plat i2c_amd_mp2_pci
[140594.217167] CPU: 5 PID: 64631 Comm: kworker/5:0 Tainted: G OE 5.4.0-33-generic #37-Ubuntu
[140594.217169] Hardware name: HP HP EliteBook 755 G5/83D5, BIOS Q81 Ver. 01.10.00 01/03/2020
[140594.217183] Workqueue: events drm_dp_destroy_connector_work [drm_kms_helper]
[140594.217187] RIP: 0010:sysfs_remove_group+0x7c/0x80
[140594.217191] Code: e7 e8 98 b9 ff ff 5b 41 5c 41 5d 5d c3 4c 89 e7 e8 e9 b4 ff ff eb c9 49 8b 55 00 48 8b 33 48 c7 c7 40 d4 58 a5 e8 4f 90 d1 ff <0f> 0b eb d8 0f 1f 44 00 00 48 85 f6 74 37 55 48 89 e5 41 55 41 54
[140594.217192] RSP: 0018:ffffb1ea82f3fc00 EFLAGS: 00010286
[140594.217194] RAX: 0000000000000000 RBX: ffffffffa52f3b60 RCX: 0000000000000006
[140594.217196] RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff9085dfd578c0
[140594.217197] RBP: ffffb1ea82f3fc18 R08: 0000000000000851 R09: 0000000000000004
[140594.217198] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
[140594.217199] R13: ffff9082e1c93800 R14: ffffffffc0327140 R15: ffffffffc0327140
[140594.217201] FS: 0000000000000000(0000) GS:ffff9085dfd40000(0000) knlGS:0000000000000000
[140594.217202] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[140594.217204] CR2: 00007f81ed808000 CR3: 000000041687e000 CR4: 00000000003406a0
[140594.217205] Call Trace:
[140594.217213] dpm_sysfs_remove+0x59/0x60
[140594.217217] device_del+0x85/0x370
[140594.217220] ? cl...

[Kai-Heng Feng (kaihengfeng)]

Please test latest mainline kernel:
https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.8-rc3/

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]