------------[ cut here ]------------
WARNING: CPU: 1 PID: 5891 at fs/quota/dquot.c:880 dqput+0x35e/0x490
Modules linked in:
CPU: 1 UID: 0 PID: 5891 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: events qsync_work_fn
RIP: 0010:dqput+0x35e/0x490
Code: da 69 ff eb 05 e8 92 da 69 ff 48 c7 c7 40 69 e1 8d 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d e9 f8 6b 26 09 e8 73 da 69 ff 90 <0f> 0b 90 e9 70 fe ff ff 48 c7 c1 7c bb a3 8f 80 e1 07 80 c1 03 38
RSP: 0018:ffffc9000393f9b0 EFLAGS: 00010293
RAX: ffffffff8255d11d RBX: ffff88811b0b6110 RCX: ffff888107a05640
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffff88811b0b6113 R09: 1ffff11023616c22
R10: dffffc0000000000 R11: ffffed1023616c23 R12: 1ffff11023616c22
R13: 1ffff11023616c04 R14: ffff88811b0b6000 R15: ffff88811b0b6020
FS:  0000000000000000(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f761445b000 CR3: 000000003b09e000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 dquot_scan_active+0x148/0x260
 qsync_work_fn+0xab/0x150
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
