[btrfs?] WARNING in btrfs_free_fs_root

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1356b5d8480000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=81c4a7c3a96074900328
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98c0bdb4abb3/disk-3f8a27f9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ea228ff02669/vmlinux-3f8a27f9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+81c4a7...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 8155 at fs/btrfs/disk-io.c:3852 btrfs_free_fs_root.cold+0x11/0x18 fs/btrfs/disk-io.c:3852
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 8155 Comm: syz-executor.2 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
panic+0x26a/0x50e kernel/panic.c:186
__warn.cold+0x20/0x5a kernel/panic.c:541
report_bug+0x262/0x2b0 lib/bug.c:183
fixup_bug arch/x86/kernel/traps.c:178 [inline]
fixup_bug arch/x86/kernel/traps.c:173 [inline]
do_error_trap+0x1d7/0x310 arch/x86/kernel/traps.c:296
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:btrfs_free_fs_root.cold+0x11/0x18 fs/btrfs/disk-io.c:3852
Code: 00 00 48 c7 c6 80 a4 a4 88 41 bc fb ff ff ff e8 63 9a ff ff e9 9a 27 eb fa e8 9a 3f 68 f9 48 c7 c7 40 74 a4 88 e8 f9 70 f9 ff <0f> 0b e9 6c 4d eb fa e8 82 3f 68 f9 48 c7 c7 40 74 a4 88 e8 e1 70
RSP: 0018:ffff88808f95faf8 EFLAGS: 00010286
RAX: 0000000000000024 RBX: ffff88808f95fb58 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff814dff01 RDI: ffffed1011f2bf51
RBP: ffff8880aff3a880 R08: 0000000000000024 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: ffff888043f6c5c0
R13: ffff8880476f07c0 R14: dffffc0000000000 R15: ffff88808f95fb50
btrfs_free_fs_roots+0x2ef/0x4d0 fs/btrfs/disk-io.c:2092
close_ctree+0x306/0x850 fs/btrfs/disk-io.c:4017
generic_shutdown_super+0x144/0x370 fs/super.c:456
kill_anon_super+0x36/0x60 fs/super.c:1032
btrfs_kill_super+0x49/0x550 fs/btrfs/super.c:2221
deactivate_locked_super+0x94/0x160 fs/super.c:329
deactivate_super+0x174/0x1a0 fs/super.c:360
cleanup_mnt+0x1a8/0x290 fs/namespace.c:1098
task_work_run+0x148/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:193 [inline]
exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f7965600517
Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 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 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeeebb4818 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f7965600517
RDX: 00007ffeeebb48e9 RSI: 000000000000000a RDI: 00007ffeeebb48e0
RBP: 00007ffeeebb48e0 R08: 00000000ffffffff R09: 00007ffeeebb46b0
R10: 000055555661b8e3 R11: 0000000000000246 R12: 00007f7965659b24
R13: 00007ffeeebb59a0 R14: 000055555661b810 R15: 00007ffeeebb59e0
Kernel Offset: disabled
Rebooting in 86400 seconds..


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