WARNING in srp_remove_one

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    f8788d86 Linux 5.6-rc3
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11c1ad29e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9833e26bab355358
dashboard link: https://syzkaller.appspot.com/bug?extid=687bc62a84a6a2a3555a
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+687bc62a84a6a2a3555a@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
sysfs group 'power' not found for kobject 'srp-syz0-1'
WARNING: CPU: 1 PID: 9946 at fs/sysfs/group.c:278 sysfs_remove_group fs/sysfs/group.c:278 [inline]
WARNING: CPU: 1 PID: 9946 at fs/sysfs/group.c:278 sysfs_remove_group+0x15b/0x1b0 fs/sysfs/group.c:269
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 9946 Comm: kworker/u4:6 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound ib_unregister_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x3e kernel/panic.c:582
 report_bug+0x289/0x300 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 fixup_bug arch/x86/kernel/traps.c:169 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:sysfs_remove_group fs/sysfs/group.c:278 [inline]
RIP: 0010:sysfs_remove_group+0x15b/0x1b0 fs/sysfs/group.c:269
Code: 48 89 d9 49 8b 55 00 48 b8 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 01 00 75 41 48 8b 33 48 c7 c7 20 9f 59 88 e8 b4 a9 5b ff <0f> 0b eb 92 e8 bc fd c9 ff e9 d0 fe ff ff 48 89 df e8 af fd c9 ff
RSP: 0018:ffffc90007d9fa98 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffffffff88b136a0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815eae46 RDI: fffff52000fb3f45
RBP: ffffc90007d9fac0 R08: ffff88809bbaa340 R09: ffffed1015d26659
R10: ffffed1015d26658 R11: ffff8880ae9332c7 R12: 0000000000000000
R13: ffff88809b4c6010 R14: ffffffff88b13c40 R15: ffffffff8a5fef80
 dpm_sysfs_remove+0x9f/0xb0 drivers/base/power/sysfs.c:741
 device_del+0x197/0xda0 drivers/base/core.c:2641
 device_unregister+0x16/0x40 drivers/base/core.c:2696
 srp_remove_one+0xad/0x250 drivers/infiniband/ulp/srp/ib_srp.c:4232
 remove_client_context+0xc7/0x120 drivers/infiniband/core/device.c:724
 disable_device+0x14c/0x230 drivers/infiniband/core/device.c:1268
 __ib_unregister_device+0x9c/0x190 drivers/infiniband/core/device.c:1435
 ib_unregister_work+0x19/0x30 drivers/infiniband/core/device.c:1545
 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264
 worker_thread+0x98/0xe40 kernel/workqueue.c:2410
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..


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