------------[ cut here ]------------
WARNING: CPU: 0 PID: 5812 at fs/btrfs/block-rsv.c:465 btrfs_release_global_block_rsv+0x254/0x270
Modules linked in:
CPU: 0 UID: 0 PID: 5812 Comm: syz-executor 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
RIP: 0010:btrfs_release_global_block_rsv+0x254/0x270
Code: 0f 0b 90 e9 e1 fe ff ff e8 39 13 cf fd 90 0f 0b 90 e9 0b ff ff ff e8 2b 13 cf fd 90 0f 0b 90 e9 35 ff ff ff e8 1d 13 cf fd 90 <0f> 0b 90 e9 66 ff ff ff e8 0f 13 cf fd 90 0f 0b 90 eb 88 66 0f 1f
RSP: 0018:ffffc90003f77ad0 EFLAGS: 00010293
RAX: ffffffff83f0f0a3 RBX: ffff88816aae8400 RCX: ffff88810ab49d00
RDX: 0000000000000000 RSI: 0000000000018000 RDI: 0000000000000000
RBP: ffff88816aae8188 R08: ffff888020bea823 R09: 1ffff1100417d504
R10: dffffc0000000000 R11: ffffed100417d505 R12: ffff88816aae8180
R13: ffff888020beb31c R14: 0000000000018000 R15: dffffc0000000000
FS:  000055555d262500(0000) GS:ffff88818eb38000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555d27d5c8 CR3: 000000001e00a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 btrfs_free_block_groups+0xc2c/0xf40
 close_ctree+0x7bc/0x1380
 generic_shutdown_super+0x135/0x2c0
 kill_anon_super+0x3b/0x70
 btrfs_kill_super+0x41/0x50
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xe9/0x130
 do_syscall_64+0x2bd/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f675ff909f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe659f1d58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f6760011d7d RCX: 00007f675ff909f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe659f1e10
RBP: 00007ffe659f1e10 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe659f2ea0
R13: 00007f6760011d7d R14: 0000000000011b6e R15: 00007ffe659f2ee0
 </TASK>
