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WARNING: CPU: 0 PID: 8397 at fs/btrfs/volumes.c:1168 close_fs_devices+0x763/0x880 fs/btrfs/volumes.c:1168
Modules linked in:
CPU: 1 PID: 8397 Comm: syz-executor.4 Not tainted 5.12.0-rc8-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 15 c6 1c fe 0f 0b e9 29 f9 ff ff e8 09 c6 1c fe 0f 0b e9 3c ff ff ff e8 fd c5 1c fe <0f> 0b e9 69 ff ff ff 48 c7 c1 54 fb 14 8e 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc9000179fb90 EFLAGS: 00010293
RAX: ffffffff8361c563 RBX: 0000000000000001 RCX: ffff888012c29c40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88802c5a2108 R08: ffffffff8361c4c5 R09: ffffed1004e49b28
R10: ffffed1004e49b28 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff88802724d868 R14: 1ffff11004e49b0d R15: 1ffff11004e49b0a
FS:  0000000001c77400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f95f567b000 CR3: 000000007796d000 CR4: 00000000001506e0
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+0x686/0x7ed fs/btrfs/disk-io.c:4343
 generic_shutdown_super+0x120/0x2a0 fs/super.c:464
 kill_anon_super+0x36/0x60 fs/super.c:1056
 btrfs_kill_super+0x3d/0x50 fs/btrfs/super.c:2353
 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:140
 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+0x10b/0x1e0 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4678b7
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:00007ffcbaa5b0f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000004678b7
RDX: 00007ffcbaa5b1cc RSI: 0000000000000002 RDI: 00007ffcbaa5b1c0
RBP: 00007ffcbaa5b1c0 R08: 00000000ffffffff R09: 00007ffcbaa5af90
R10: 0000000001c788e3 R11: 0000000000000246 R12: 00000000004bebb2
R13: 00007ffcbaa5c290 R14: 0000000001c78810 R15: 00007ffcbaa5c2d0