PROBLEM: nfs? crash in Linux 5.3 (possible regression)

[Nick Bowler]

Hi all,

I hit this oops on Linux 5.3 yesterday.  The crash itself occurred while
compiling Linux (source and build dirs on NFS).  Afterwards, the system
remained mostly alive but my NFS mounts became very busted with lots
(but not all) I/O operations appearing to hang forever.

Not sure how reproducible this is.  Since I've never seen a crash
like this before it may be a regression compared to, say, Linux 4.19
but I am not certain because this particular machine is brand new so
I don't have experience with older kernels on it...

Full dmesg is attached (gzipped).

Let me know if you need any more info.

[  796.050025] BUG: kernel NULL pointer dereference, address: 0000000000000014
[  796.051280] #PF: supervisor read access in kernel mode
[  796.053063] #PF: error_code(0x0000) - not-present page
[  796.054636] PGD 0 P4D 0
[  796.055688] Oops: 0000 [#1] PREEMPT SMP
[  796.056768] CPU: 2 PID: 190 Comm: kworker/2:2 Tainted: G        W
      5.3.0 #6
[  796.057953] Hardware name: To Be Filled By O.E.M. To Be Filled By
O.E.M./B450 Gaming-ITX/ac, BIOS P3.30 05/17/2019
[  796.059329] Workqueue: events key_garbage_collector
[  796.060623] RIP: 0010:keyring_gc_check_iterator+0x27/0x30
[  796.061845] Code: 44 00 00 48 83 e7 fc b8 01 00 00 00 f6 87 80 00
00 00 21 75 19 48 8b 57 58 48 39 16 7c 05 48 85 d2 7f 0b 48 8b 87 a0
00 00 00 <0f> b6 40 14 c3 0f 1f 40 00 48 83 e7 fc e9 27 eb ff ff 0f 1f
80 00
[  796.064638] RSP: 0018:ffffb40fc0757df8 EFLAGS: 00010282
[  796.066058] RAX: 0000000000000000 RBX: ffffa14338caed80 RCX: ffffb40fc0757e40
[  796.067531] RDX: ffffa1433ae85558 RSI: ffffb40fc0757e40 RDI: ffffa1433ae85500
[  796.069014] RBP: ffffb40fc0757e40 R08: 0000000000000000 R09: 000000000000000f
[  796.070513] R10: 8080808080808080 R11: 0000000000000001 R12: ffffffffa4cd6180
[  796.072025] R13: ffffa14338caee10 R14: ffffa14338caedf0 R15: ffffa1433ffeff00
[  796.073567] FS:  0000000000000000(0000) GS:ffffa14340480000(0000)
knlGS:0000000000000000
[  796.075171] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  796.076785] CR2: 0000000000000014 CR3: 0000000747ce6000 CR4: 00000000003406e0
[  796.078445] Call Trace:
[  796.080091]  assoc_array_subtree_iterate+0x55/0x100
[  796.081770]  keyring_gc+0x3f/0x80
[  796.083447]  key_garbage_collector+0x330/0x3d0
[  796.085155]  process_one_work+0x1cb/0x320
[  796.086869]  worker_thread+0x28/0x3c0
[  796.088603]  ? process_one_work+0x320/0x320
[  796.090335]  kthread+0x106/0x120
[  796.092053]  ? kthread_create_on_node+0x40/0x40
[  796.093810]  ret_from_fork+0x1f/0x30
[  796.095569] Modules linked in: sha1_ssse3 sha1_generic cbc cts
rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs lockd grace ext4 crc16 mbcache
jbd2 iwlmvm mac80211 libarc4 amdgpu iwlwifi snd_hda_codec_realtek
snd_hda_codec_generic kvm_amd gpu_sched kvm snd_hda_codec_hdmi
drm_kms_helper irqbypass k10temp syscopyarea sysfillrect sysimgblt
fb_sys_fops video ttm cfg80211 snd_hda_intel snd_hda_codec drm
snd_hwdep rfkill snd_hda_core backlight snd_pcm evdev snd_timer snd
soundcore efivarfs dm_crypt hid_generic igb hwmon i2c_algo_bit sr_mod
cdrom sunrpc dm_mod
[  796.104033] CR2: 0000000000000014
[  796.106304] ---[ end trace 695aee10f9202347 ]---
[  796.108585] RIP: 0010:keyring_gc_check_iterator+0x27/0x30
[  796.110894] Code: 44 00 00 48 83 e7 fc b8 01 00 00 00 f6 87 80 00
00 00 21 75 19 48 8b 57 58 48 39 16 7c 05 48 85 d2 7f 0b 48 8b 87 a0
00 00 00 <0f> b6 40 14 c3 0f 1f 40 00 48 83 e7 fc e9 27 eb ff ff 0f 1f
80 00
[  796.115773] RSP: 0018:ffffb40fc0757df8 EFLAGS: 00010282
[  796.118209] RAX: 0000000000000000 RBX: ffffa14338caed80 RCX: ffffb40fc0757e40
[  796.120683] RDX: ffffa1433ae85558 RSI: ffffb40fc0757e40 RDI: ffffa1433ae85500
[  796.123176] RBP: ffffb40fc0757e40 R08: 0000000000000000 R09: 000000000000000f
[  796.125668] R10: 8080808080808080 R11: 0000000000000001 R12: ffffffffa4cd6180
[  796.128104] R13: ffffa14338caee10 R14: ffffa14338caedf0 R15: ffffa1433ffeff00
[  796.130493] FS:  0000000000000000(0000) GS:ffffa14340480000(0000)
knlGS:0000000000000000
[  796.132923] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  796.135266] CR2: 0000000000000014 CR3: 0000000747ce6000 CR4: 00000000003406e0

Thanks,
  Nick

Attachment: atlas-crash.log.gz
Description: GNU Zip compressed data