WARNING: fs/kernfs/dir.c:1508 kernfs_remove_by_name_ns

[Naresh Kamboju]

Kernel WARNING noticed on arm64 db410c device while booting linux next
20200721 tag.
Kernel BUGs followed by kernel WARNINGS noticed on this db410c device.

metadata:
  git branch: master
  git repo: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
  git commit: de2e69cfe54a8f2ed4b75f09d3110c514f45d38e
  git describe: next-20200721
  kernel-config:
http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/dragonboard-410c/lkft/linux-next/818/config
  build-location:
http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/dragonboard-410c/lkft/linux-next/818

Crash log:
[    5.802135] ------------[ cut here ]------------
[    5.802509] l12: supplied by regulator-dummy
[    5.805901] kernfs: can not remove 'supplier:regulator.14', no directory
[    5.810782] l12: Bringing 0uV into 1750000-1750000uV
[    5.814789] WARNING: CPU: 3 PID: 164 at
/usr/src/kernel/fs/kernfs/dir.c:1508
kernfs_remove_by_name_ns+0xb0/0xc0
[    5.823085] l13: supplied by regulator-dummy
[    5.826334] Modules linked in:
[    5.826354] CPU: 3 PID: 164 Comm: kworker/3:2 Tainted: G        W
      5.8.0-rc6-next-20200721 #1
[    5.826363] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
[    5.826378] Workqueue: rcu_gp srcu_invoke_callbacks
[    5.826396] pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--)
[    5.826409] pc : kernfs_remove_by_name_ns+0xb0/0xc0
[    5.836530] l13: Bringing 0uV into 1750000-1750000uV
[    5.840651] lr : kernfs_remove_by_name_ns+0xb0/0xc0
[    5.840659] sp : ffff800014093be0
[    5.840667] x29: ffff800014093be0 x28: 0000000000000000
[    5.840688] x27: ffff8000101c42cc x26: ffff8000101c42cc
[    5.840708] x25: ffff8000129fee68 x24: ffff00003fcb7640
[    5.845080] l14: supplied by regulator-dummy
[    5.852811] x23: ffff00003fcb76c0 x22: 0000000000000000
[    5.852831] x21: ffff00003a5cb400 x20: 0000000000000000
[    5.852851] x19: ffff00003a604018 x18: ffffffffffffffff
[    5.852875] x17: 0000000000000000
[    5.859830] l14: Bringing 0uV into 1750000-1750000uV
[    5.864089] x16: 0000000000000000
[    5.864102] x15: ffff800012720a88 x14: ffff800094093877
[    5.864123] x13: ffff800014093885 x12: 0000000000000003
[    5.864143] x11: 0000000005f5e0ff x10: 0000000000000000
[    5.871315] l15: supplied by regulator-dummy
[    5.874505] x9 : ffff800012720a88 x8 : 0000000018bc90a0
[    5.874526] x7 : 00000000b9433f15 x6 : ffff800014093820
[    5.874546] x5 : ffff800012721000 x4 : 0000000000000003
[    5.874566] x3 : 0000000000000004 x2 : 0000000000000201
[    5.880082] l15: Bringing 0uV into 1750000-1750000uV
[    5.884311] x1 : b2684f8263e0e600 x0 : 0000000000000000
[    5.884333] Call trace:
[    5.884346]  kernfs_remove_by_name_ns+0xb0/0xc0
[    5.884358]  sysfs_remove_link+0x30/0x60
[    5.884371]  devlink_remove_symlinks+0xa8/0x138
[    5.884382]  device_del+0xf4/0x3c0
[    5.890179] l16: supplied by regulator-dummy
[    5.893172]  device_unregister+0x24/0x78
[    5.893182]  __device_link_free_srcu+0x64/0x70
[    5.898780] l16: Bringing 0uV into 1750000-1750000uV
[    5.903762]  srcu_invoke_callbacks+0x10c/0x1a0
[    5.903773]  process_one_work+0x2b0/0x768
[    5.903783]  worker_thread+0x48/0x498
[    5.903795]  kthread+0x158/0x168
[    5.903806]  ret_from_fork+0x10/0x1c
[    5.903815] irq event stamp: 18695
[    5.909658] l17: supplied by regulator-dummy
[    5.913312] hardirqs last  enabled at (18694): [<ffff800010083318>]
el1_irq+0xd8/0x180
[    5.913325] hardirqs last disabled at (18695): [<ffff8000100aaebc>]
debug_exception_enter+0xac/0xe8
[    5.913337] softirqs last  enabled at (18614): [<ffff8000101c42cc>]
srcu_invoke_callbacks+0xf4/0x1a0
[    5.913349] softirqs last disabled at (18652): [<ffff8000101c42cc>]
srcu_invoke_callbacks+0xf4/0x1a0
[    5.913358] ---[ end trace 8fa12bb0128735e5 ]---

full test log,
https://qa-reports.linaro.org/lkft/linux-next-oe/build/next-20200721/testrun/2972385/suite/linux-log-parser/test/check-kernel-warning-1595062/log

--
Linaro LKFT
https://lkft.linaro.org