BTRFS error (device loop0): failed to run delayed ref for logical 5369856 num_bytes 4096 type 178 action 1 ref_mod 1: -2
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BTRFS: Transaction aborted (error -2)
WARNING: fs/btrfs/extent-tree.c:2247 at btrfs_run_delayed_refs+0x30b/0x3b0 fs/btrfs/extent-tree.c:2247, CPU#0: kworker/u4:6/175
Modules linked in:
CPU: 0 UID: 0 PID: 175 Comm: kworker/u4:6 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_refs+0x30e/0x3b0 fs/btrfs/extent-tree.c:2247
Code: 85 e4 75 07 e8 03 60 dd fd eb 7a e8 0c 6c c2 fd 84 c0 74 20 e8 f3 5f dd fd eb 6a e8 ec 5f dd fd 48 8d 3d 25 8a 51 0c 44 89 fe <67> 48 0f b9 3a e9 0b ff ff ff e8 c3 bf c1 07 41 89 c4 31 ff 89 c6
RSP: 0018:ffffc900017f77b8 EFLAGS: 00010293
RAX: ffffffff83e85ab4 RBX: ffff8880477018f8 RCX: ffff888032e94a00
RDX: 0000000000000000 RSI: 00000000fffffffe RDI: ffffffff9039e4e0
RBP: 0000000000000000 R08: ffff888032e94a00 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000000 R12: ffff888040990001
R13: ffff888012cce000 R14: dffffc0000000000 R15: 00000000fffffffe
FS:  0000000000000000(0000) GS:ffff88808c887000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff607438120 CR3: 0000000011dc3000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 flush_space+0x574/0xe20 fs/btrfs/space-info.c:-1
 do_async_reclaim_metadata_space+0x3fc/0x960 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:3302 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
 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>
----------------
Code disassembly (best guess):
   0:	85 e4                	test   %esp,%esp
   2:	75 07                	jne    0xb
   4:	e8 03 60 dd fd       	call   0xfddd600c
   9:	eb 7a                	jmp    0x85
   b:	e8 0c 6c c2 fd       	call   0xfdc26c1c
  10:	84 c0                	test   %al,%al
  12:	74 20                	je     0x34
  14:	e8 f3 5f dd fd       	call   0xfddd600c
  19:	eb 6a                	jmp    0x85
  1b:	e8 ec 5f dd fd       	call   0xfddd600c
  20:	48 8d 3d 25 8a 51 0c 	lea    0xc518a25(%rip),%rdi        # 0xc518a4c
  27:	44 89 fe             	mov    %r15d,%esi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 0b ff ff ff       	jmp    0xffffff3f
  34:	e8 c3 bf c1 07       	call   0x7c1bffc
  39:	41 89 c4             	mov    %eax,%r12d
  3c:	31 ff                	xor    %edi,%edi
  3e:	89 c6                	mov    %eax,%esi