------------[ cut here ]------------
BTRFS: Transaction aborted (error -28)
WARNING: fs/btrfs/block-group.c:4141 at do_chunk_alloc fs/btrfs/block-group.c:4141 [inline], CPU#0: kworker/u4:0/12
WARNING: fs/btrfs/block-group.c:4141 at btrfs_chunk_alloc+0x101d/0x15e0 fs/btrfs/block-group.c:4382, 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:do_chunk_alloc fs/btrfs/block-group.c:4141 [inline]
RIP: 0010:btrfs_chunk_alloc+0x101f/0x15e0 fs/btrfs/block-group.c:4382
Code: 17 2a b1 fd e9 6d 01 00 00 e8 fd 2c 96 fd 84 c0 74 22 e8 04 2a b1 fd e9 5a 01 00 00 e8 fa 29 b1 fd 48 8d 3d a3 06 07 0c 89 de <67> 48 0f b9 3a e9 b3 fc ff ff e8 52 a3 9c 07 41 89 c6 31 ff 89 c6
RSP: 0000:ffffc9000025f6d0 EFLAGS: 00010293
RAX: ffffffff84149496 RBX: ffffffffffffffe4 RCX: ffff88801cad4980
RDX: 0000000000000000 RSI: 00000000ffffffe4 RDI: ffffffff901b9b40
RBP: 0000000000000000 R08: ffff88801cad4980 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000000 R12: 1ffff110084e3916
R13: ffff8880118a99a0 R14: ffff8880429f0001 R15: ffff8880407da800
FS:  0000000000000000(0000) GS:ffff88808ca4c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f38f0cbb3d0 CR3: 00000000441fe000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 flush_space+0x353/0xd80 fs/btrfs/space-info.c:896
 do_async_reclaim_metadata_space+0x3fc/0x960 fs/btrfs/space-info.c:1187
 btrfs_async_reclaim_metadata_space+0x89/0xe0 fs/btrfs/space-info.c:1254
 process_one_work kernel/workqueue.c:3276 [inline]
 process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	2a b1 fd e9 6d 01    	sub    0x16de9fd(%rcx),%dh
   6:	00 00                	add    %al,(%rax)
   8:	e8 fd 2c 96 fd       	call   0xfd962d0a
   d:	84 c0                	test   %al,%al
   f:	74 22                	je     0x33
  11:	e8 04 2a b1 fd       	call   0xfdb12a1a
  16:	e9 5a 01 00 00       	jmp    0x175
  1b:	e8 fa 29 b1 fd       	call   0xfdb12a1a
  20:	48 8d 3d a3 06 07 0c 	lea    0xc0706a3(%rip),%rdi        # 0xc0706ca
  27:	89 de                	mov    %ebx,%esi
* 29:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2e:	e9 b3 fc ff ff       	jmp    0xfffffce6
  33:	e8 52 a3 9c 07       	call   0x79ca38a
  38:	41 89 c6             	mov    %eax,%r14d
  3b:	31 ff                	xor    %edi,%edi
  3d:	89 c6                	mov    %eax,%esi