VFS: Busy inodes after unmount of loop4 (btrfs)
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kernel BUG at fs/super.c:651!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 PID: 11717 Comm: syz-executor.4 Not tainted 6.9.0-rc6-syzkaller-00227-g3d25a941ea50 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:generic_shutdown_super+0x2c7/0x2d0 fs/super.c:649
Code: 1b 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 5c 71 ee ff 48 8b 13 48 c7 c7 c0 17 d8 8b 4c 89 e6 e8 1a af 6b 09 90 <0f> 0b 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90006f27d08 EFLAGS: 00010246
RAX: 000000000000002f RBX: ffffffff8e86edc0 RCX: 57576f3327284f00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 1ffff1100e9714f1 R08: ffffffff8176b5ec R09: fffffbfff1c39b5c
R10: dffffc0000000000 R11: fffffbfff1c39b5c R12: ffff888074b8a668
R13: dffffc0000000000 R14: ffffffff8c0ab0f8 R15: ffff888074b8a788
FS:  0000555568b47480(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7462f015e3 CR3: 0000000023c16000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kill_anon_super+0x3b/0x70 fs/super.c:1225
 btrfs_kill_super+0x41/0x50 fs/btrfs/super.c:2091
 deactivate_locked_super+0xc4/0x130 fs/super.c:472
 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267
 task_work_run+0x24f/0x310 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3df127efd7
Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fff26095538 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f3df127efd7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff260955f0
RBP: 00007fff260955f0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff260966b0
R13: 00007f3df12c83b9 R14: 00000000000651f6 R15: 0000000000000006
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:generic_shutdown_super+0x2c7/0x2d0 fs/super.c:649
Code: 1b 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 5c 71 ee ff 48 8b 13 48 c7 c7 c0 17 d8 8b 4c 89 e6 e8 1a af 6b 09 90 <0f> 0b 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90006f27d08 EFLAGS: 00010246
RAX: 000000000000002f RBX: ffffffff8e86edc0 RCX: 57576f3327284f00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 1ffff1100e9714f1 R08: ffffffff8176b5ec R09: fffffbfff1c39b5c
R10: dffffc0000000000 R11: fffffbfff1c39b5c R12: ffff888074b8a668
R13: dffffc0000000000 R14: ffffffff8c0ab0f8 R15: ffff888074b8a788
FS:  0000555568b47480(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31031000 CR3: 0000000023c16000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400