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WARNING: CPU: 2 PID: 8747 at fs/btrfs/volumes.c:1172 close_fs_devices+0x71d/0x930 fs/btrfs/volumes.c:1172
Modules linked in:
CPU: 2 PID: 8747 Comm: syz-executor.2 Not tainted 5.11.0-rc6-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:close_fs_devices+0x71d/0x930 fs/btrfs/volumes.c:1172
Code: e8 a8 a8 3f fe 85 db 0f 85 5d f9 ff ff e8 1b a1 3f fe 0f 0b e9 51 f9 ff ff e8 0f a1 3f fe 0f 0b e9 c0 fe ff ff e8 03 a1 3f fe <0f> 0b e9 f9 fe ff ff 48 c7 c7 5c bc 03 8d e8 40 66 82 fe e9 11 f9
RSP: 0018:ffffc90000e37bb8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff888015038000 RSI: ffffffff83331a6d RDI: 0000000000000003
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffff888020d2893b
R10: ffffffff83331964 R11: 0000000000000001 R12: ffff888020d28938
R13: ffff888020d289f4 R14: ffff888013774508 R15: ffff888020d28850
FS:  0000000000000000(0000) GS:ffff88802cc00000(0063) knlGS:0000000009bf7380
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000002d122000 CR3: 0000000064a7c000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 btrfs_close_devices+0x8e/0x4b0 fs/btrfs/volumes.c:1184
 close_ctree+0x6bd/0x700 fs/btrfs/disk-io.c:4208
 generic_shutdown_super+0x144/0x370 fs/super.c:464
 kill_anon_super+0x36/0x60 fs/super.c:1055
 btrfs_kill_super+0x38/0x50 fs/btrfs/super.c:2347
 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: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+0x249/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 __do_fast_syscall_32+0x62/0x80 arch/x86/entry/common.c:142
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:164
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7ff0549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000ff9a7cac EFLAGS: 00000292 ORIG_RAX: 0000000000000034
RAX: 0000000000000000 RBX: 00000000ff9a7d50 RCX: 0000000000000002
RDX: 0000000008164000 RSI: 0000000000000000 RDI: 00000000080db4e8
RBP: 00000000ff9a7d50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000