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WARNING: CPU: 0 PID: 8432 at fs/btrfs/volumes.c:1168 close_fs_devices+0x772/0x9a0 fs/btrfs/volumes.c:1168
Modules linked in:
CPU: 0 PID: 8432 Comm: syz-executor.0 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:close_fs_devices+0x772/0x9a0 fs/btrfs/volumes.c:1168
Code: e8 d3 27 34 fe 85 db 0f 85 07 f9 ff ff e8 16 20 34 fe 0f 0b e9 fb f8 ff ff e8 0a 20 34 fe 0f 0b e9 e2 fd ff ff e8 fe 1f 34 fe <0f> 0b e9 19 fe ff ff 48 c7 c7 ac 9c c9 8d e8 db 29 79 fe e9 bb f8
RSP: 0018:ffffc9000193fbd0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff8880261b9c40 RSI: ffffffff8340bc82 RDI: 0000000000000003
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffff88802014613b
R10: ffffffff8340ba99 R11: 0000000000000000 R12: ffff888020146138
R13: 0000000000000000 R14: ffff888034d8d508 R15: ffff888020146050
FS:  0000000001b2a400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000970004 CR3: 0000000066015000 CR4: 0000000000350ef0
Call Trace:
 btrfs_close_devices+0x8e/0x4b0 fs/btrfs/volumes.c:1180
 close_ctree+0x752/0x795 fs/btrfs/disk-io.c:4439
 generic_shutdown_super+0x14c/0x370 fs/super.c:465
 kill_anon_super+0x36/0x60 fs/super.c:1057
 btrfs_kill_super+0x38/0x50 fs/btrfs/super.c:2379
 deactivate_locked_super+0x94/0x160 fs/super.c:335
 deactivate_super+0xad/0xd0 fs/super.c:366
 cleanup_mnt+0x3a2/0x540 fs/namespace.c:1136
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x272/0x280 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x467a37
Code: ff d0 48 89 c7 b8 3c 00 00 00 0f 05 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe955000b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000467a37
RDX: 00007ffe9550018b RSI: 0000000000000002 RDI: 00007ffe95500180
RBP: 00007ffe95500180 R08: 00000000ffffffff R09: 00007ffe954fff50
R10: 0000000001b2b8e3 R11: 0000000000000246 R12: 00000000004bee70
R13: 00007ffe95501250 R14: 0000000001b2b810 R15: 00007ffe95501290