------------[ cut here ]------------
BTRFS: Transaction aborted (error -28)
WARNING: fs/btrfs/block-group.c:4175 at do_chunk_alloc fs/btrfs/block-group.c:4175 [inline], CPU#0: kworker/u4:7/1061
WARNING: fs/btrfs/block-group.c:4175 at btrfs_chunk_alloc+0x101d/0x15e0 fs/btrfs/block-group.c:4416, CPU#0: kworker/u4:7/1061
Modules linked in:
CPU: 0 UID: 0 PID: 1061 Comm: kworker/u4:7 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:do_chunk_alloc fs/btrfs/block-group.c:4175 [inline]
RIP: 0010:btrfs_chunk_alloc+0x101f/0x15e0 fs/btrfs/block-group.c:4416
Code: c7 60 ad fd e9 6d 01 00 00 e8 cd 67 92 fd 84 c0 74 22 e8 b4 60 ad fd e9 5a 01 00 00 e8 aa 60 ad fd 48 8d 3d 13 be 21 0c 89 de <67> 48 0f b9 3a e9 b3 fc ff ff e8 22 14 91 07 41 89 c6 31 ff 89 c6
RSP: 0018:ffffc90000e8f6d0 EFLAGS: 00010293
RAX: ffffffff84186666 RBX: ffffffffffffffe4 RCX: ffff88803695a540
RDX: 0000000000000000 RSI: 00000000ffffffe4 RDI: ffffffff903a2480
RBP: 0000000000000000 R08: ffff88803695a540 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000000 R12: 1ffff11008420516
R13: ffff888054c76c20 R14: ffff888055118001 R15: ffff8880553cc000
FS:  0000000000000000(0000) GS:ffff88808c894000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6b1f4e3840 CR3: 0000000041ef4000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 flush_space+0x3fb/0xe20 fs/btrfs/space-info.c:908
 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:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x389/0x470 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), 2 bytes skipped:
   0:	ad                   	lods   %ds:(%rsi),%eax
   1:	fd                   	std
   2:	e9 6d 01 00 00       	jmp    0x174
   7:	e8 cd 67 92 fd       	call   0xfd9267d9
   c:	84 c0                	test   %al,%al
   e:	74 22                	je     0x32
  10:	e8 b4 60 ad fd       	call   0xfdad60c9
  15:	e9 5a 01 00 00       	jmp    0x174
  1a:	e8 aa 60 ad fd       	call   0xfdad60c9
  1f:	48 8d 3d 13 be 21 0c 	lea    0xc21be13(%rip),%rdi        # 0xc21be39
  26:	89 de                	mov    %ebx,%esi
* 28:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2d:	e9 b3 fc ff ff       	jmp    0xfffffce5
  32:	e8 22 14 91 07       	call   0x7911459
  37:	41 89 c6             	mov    %eax,%r14d
  3a:	31 ff                	xor    %edi,%edi
  3c:	89 c6                	mov    %eax,%esi