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WARNING: CPU: 0 PID: 8464 at fs/btrfs/volumes.c:1168 close_fs_devices+0x763/0x880 fs/btrfs/volumes.c:1168
Modules linked in:
CPU: 0 PID: 8464 Comm: syz-executor.4 Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:close_fs_devices+0x763/0x880 fs/btrfs/volumes.c:1168
Code: c4 38 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 75 28 17 fe 0f 0b e9 29 f9 ff ff e8 69 28 17 fe 0f 0b e9 3c ff ff ff e8 5d 28 17 fe <0f> 0b e9 69 ff ff ff 48 c7 c1 04 c3 39 8e 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc9000194fb70 EFLAGS: 00010293
RAX: ffffffff8368a473 RBX: 0000000000000001 RCX: ffff888027890000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff888027f85108 R08: ffffffff8368a3d5 R09: ffffed1005f8b628
R10: ffffed1005f8b628 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff88802fc5b068 R14: 1ffff11005f8b60d R15: 1ffff11005f8b60a
FS:  0000000001fbf400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4e6a38e000 CR3: 00000000883b7000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 btrfs_close_devices+0xc9/0x450 fs/btrfs/volumes.c:1180
 close_ctree+0x693/0x7fd fs/btrfs/disk-io.c:4433
 generic_shutdown_super+0x12e/0x2b0 fs/super.c:465
 kill_anon_super+0x36/0x60 fs/super.c:1057
 btrfs_kill_super+0x3d/0x50 fs/btrfs/super.c:2367
 deactivate_locked_super+0xa7/0xf0 fs/super.c:335
 cleanup_mnt+0x462/0x510 fs/namespace.c:1136
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x201/0x220 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:302
 do_syscall_64+0x4c/0xb0 arch/x86/entry/common.c:86
 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:00007ffc1142cb58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000467a37
RDX: 00007ffc1142cc2c RSI: 0000000000000002 RDI: 00007ffc1142cc20
RBP: 00007ffc1142cc20 R08: 00000000ffffffff R09: 00007ffc1142c9f0
R10: 0000000001fc08e3 R11: 0000000000000246 R12: 00000000004bee70
R13: 00007ffc1142dcf0 R14: 0000000001fc0810 R15: 00007ffc1142dd30