------------[ cut here ]------------
WARNING: CPU: 0 PID: 11848 at fs/btrfs/volumes.c:1166 close_fs_devices.part.0+0x607/0x800 fs/btrfs/volumes.c:1166
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 11848 Comm: syz-executor.0 Not tainted 5.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 panic+0x382/0x7fb kernel/panic.c:231
 __warn.cold+0x20/0x4b kernel/panic.c:600
 report_bug+0x1bd/0x210 lib/bug.c:198
 handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
 exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:close_fs_devices.part.0+0x607/0x800 fs/btrfs/volumes.c:1166
Code: 0f b6 04 02 84 c0 74 02 7e 33 48 8b 44 24 18 c6 80 30 01 00 00 00 48 83 c4 30 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 a9 35 4a fe <0f> 0b e9 71 ff ff ff e8 9d 35 4a fe 0f 0b e9 20 ff ff ff e8 41 0d
RSP: 0018:ffffc90006567c58 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: ffffffff832c0856
RDX: ffff88808d48e040 RSI: ffffffff832c08e7 RDI: 0000000000000007
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffff88809613cc7f
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888090fbc130
R13: ffff888090fbc1ec R14: ffff88809613cd08 R15: ffff888090fbc050
 close_fs_devices fs/btrfs/volumes.c:1193 [inline]
 btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1179
 close_ctree+0x688/0x6cb fs/btrfs/disk-io.c:4148
 generic_shutdown_super+0x144/0x370 fs/super.c:464
 kill_anon_super+0x36/0x60 fs/super.c:1108
 btrfs_kill_super+0x38/0x50 fs/btrfs/super.c:2265
 deactivate_locked_super+0x94/0x160 fs/super.c:335
 deactivate_super+0xad/0xd0 fs/super.c:366
 cleanup_mnt+0x3a3/0x530 fs/namespace.c:1118
 task_work_run+0xdd/0x190 kernel/task_work.c:141
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:165 [inline]
 exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:192
 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:267
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4608b7
Code: 64 89 04 25 d0 02 00 00 58 5f ff d0 48 89 c7 e8 2f be ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 ad 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff029ab998 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000004608b7
RDX: 0000000000403158 RSI: 0000000000000002 RDI: 00007fff029aba40
RBP: 000000000000048c R08: 0000000000000000 R09: 000000000000000b
R10: 0000000000000005 R11: 0000000000000246 R12: 00007fff029acad0
R13: 0000000001a0ba60 R14: 0000000000000000 R15: 00007fff029acad0
Kernel Offset: disabled
Rebooting in 86400 seconds..