BTRFS info (device loop3): last unmount of filesystem e417788f-7a09-42b2-9266-8ddc5d5d35d2
BUG: MAX_LOCKDEP_KEYS too low!
turning off the locking correctness validator.
CPU: 1 UID: 0 PID: 6046 Comm: syz-executor.3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 register_lock_class+0x419/0x4c0 kernel/locking/lockdep.c:1332
 __lock_acquire+0x9f/0x1ce0 kernel/locking/lockdep.c:5112
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825
 touch_wq_lockdep_map+0xad/0x1c0 kernel/workqueue.c:3936
 __flush_workqueue+0x128/0x1230 kernel/workqueue.c:3978
 drain_workqueue+0x199/0x3d0 kernel/workqueue.c:4142
 destroy_workqueue+0xc2/0xaa0 kernel/workqueue.c:5901
 btrfs_stop_all_workers+0x29f/0x370 fs/btrfs/disk-io.c:1785
 close_ctree+0x5c8/0x1710 fs/btrfs/disk-io.c:4410
 generic_shutdown_super+0x153/0x390 fs/super.c:642
 kill_anon_super+0x3a/0x60 fs/super.c:1281
 btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2129
 deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
 deactivate_super fs/super.c:506 [inline]
 deactivate_super+0xde/0x100 fs/super.c:502
 cleanup_mnt+0x225/0x450 fs/namespace.c:1327
 task_work_run+0x14d/0x240 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x130 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x426/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9de767f1d7
Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc76678888 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f9de76c93b9 RCX: 00007f9de767f1d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc76678940
RBP: 00007ffc76678940 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc76679a00
R13: 00007f9de76c93b9 R14: 000000000005277b R15: 0000000000000003
 </TASK>
BTRFS info (device loop3): last unmount of filesystem 3e041a67-ab35-4eaf-96e4-6ba3afd83a61
BTRFS info (device loop3): last unmount of filesystem e417788f-7a09-42b2-9266-8ddc5d5d35d2
BTRFS info (device loop3): last unmount of filesystem 905a767f-a2b4-4b67-9c7c-6a042d9069fc
BTRFS info (device loop3): last unmount of filesystem e417788f-7a09-42b2-9266-8ddc5d5d35d2
BTRFS info (device loop3): last unmount of filesystem e417788f-7a09-42b2-9266-8ddc5d5d35d2
BTRFS info (device loop3): last unmount of filesystem 9d8a6770-de65-4ed5-9374-c3ee48fdb229
BTRFS info (device loop3): last unmount of filesystem e733b540-24f6-4585-9d4e-dd45f361d637
BTRFS info (device loop3): last unmount of filesystem 0a4c4cfe-4395-421a-9846-fe5b4a0d859f