------------[ cut here ]------------
btrfs_abort_should_print_stack(__error)
WARNING: fs/btrfs/delayed-inode.c:1161 at __btrfs_run_delayed_items+0x3dd/0x420 fs/btrfs/delayed-inode.c:1161, CPU#0: kworker/u4:0/12
Modules linked in:
CPU: 0 UID: 0 PID: 12 Comm: kworker/u4:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: events_unbound btrfs_async_reclaim_metadata_space
RIP: 0010:__btrfs_run_delayed_items+0x3dd/0x420 fs/btrfs/delayed-inode.c:1161
Code: c1 38 c1 0f 8c be fc ff ff 4c 89 ff e8 9c 14 0c fe e9 b1 fc ff ff e8 c2 e0 9c fd eb 10 e8 bb e0 9c fd eb 09 e8 b4 e0 9c fd 90 <0f> 0b 90 44 89 e1 f7 d9 e9 41 ff ff ff e8 a1 e0 9c fd 48 c7 c7 60
RSP: 0018:ffffc9000025f7b0 EFLAGS: 00010293
RAX: ffffffff842a322c RBX: ffff8880443bd580 RCX: ffff88801cedca80
RDX: 0000000000000000 RSI: ffffffff8f1e9f80 RDI: 00000000ffffffe4
RBP: 0000000000000001 R08: ffff88801cedca80 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000000 R12: 00000000ffffffe4
R13: ffff8880441375a0 R14: ffff888050fd0000 R15: 1ffff11008877ab0
FS:  0000000000000000(0000) GS:ffff88808c54a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f22f3b039a0 CR3: 000000003f106000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 flush_space+0x5fd/0xde0 fs/btrfs/space-info.c:875
 do_async_reclaim_metadata_space+0x3e8/0x940 fs/btrfs/space-info.c:1211
 btrfs_async_reclaim_metadata_space+0x89/0xe0 fs/btrfs/space-info.c:1278
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>