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WARNING: CPU: 0 PID: 1381 at fs/btrfs/volumes.c:1168 close_fs_devices+0x772/0x9a0 fs/btrfs/volumes.c:1168
Modules linked in:
CPU: 0 PID: 1381 Comm: syz-executor.5 Not tainted 5.14.0-rc2-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 93 81 2f fe 85 db 0f 85 07 f9 ff ff e8 46 7a 2f fe 0f 0b e9 fb f8 ff ff e8 3a 7a 2f fe 0f 0b e9 e2 fd ff ff e8 2e 7a 2f fe <0f> 0b e9 19 fe ff ff 48 c7 c7 6c 98 6c 8d e8 cb aa 75 fe e9 bb f8
RSP: 0018:ffffc90017b27bd0 EFLAGS: 00010246
RAX: 0000000000040000 RBX: 0000000000000001 RCX: ffffc90014960000
RDX: 0000000000040000 RSI: ffffffff83460ea2 RDI: 0000000000000003
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffff88808b8ca13b
R10: ffffffff83460cb9 R11: 0000000000000000 R12: ffff88808b8ca138
R13: 0000000000000000 R14: ffff8880839a2108 R15: ffff88808b8ca050
FS:  00007f0b26639700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5018f27000 CR3: 00000000b3f92000 CR4: 0000000000350ee0
Call Trace:
 btrfs_close_devices+0x8e/0x4b0 fs/btrfs/volumes.c:1180
 close_ctree+0x752/0x795 fs/btrfs/disk-io.c:4433
 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:2367
 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:175 [inline]
 exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x467b0a
Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 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:00007f0b26638fa8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffec RBX: 0000000020000200 RCX: 0000000000467b0a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f0b26639000
RBP: 00007f0b26639040 R08: 00007f0b26639040 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f0b26639000 R15: 0000000020020600