VFS: Busy inodes after unmount of loop1 (btrfs)
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kernel BUG at fs/super.c:652!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 5831 Comm: syz-executor Not tainted 6.15.0-rc2-syzkaller-00404-g8560697b23dc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:generic_shutdown_super+0x2ca/0x2d0 fs/super.c:650
Code: 1b 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 79 bc ed ff 48 8b 13 48 c7 c7 20 e2 58 8c 4c 89 e6 e8 97 5a ea fe 90 <0f> 0b 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003fdfd10 EFLAGS: 00010246
RAX: 000000000000002f RBX: ffffffff8f2aeec0 RCX: 096803ea5bee1400
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 1ffff1100a8d1cf0 R08: ffffffff81a21cac R09: 1ffff920007fbf3c
R10: dffffc0000000000 R11: fffff520007fbf3d R12: ffff88805468e668
R13: dffffc0000000000 R14: ffffffff8c8c4c98 R15: ffff88805468e780
FS:  000055555dc2a500(0000) GS:ffff8881250cf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556505a9d018 CR3: 000000006e726000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kill_anon_super+0x3b/0x70 fs/super.c:1237
 btrfs_kill_super+0x41/0x50 fs/btrfs/super.c:2099
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x422/0x4c0 fs/namespace.c:1435
 task_work_run+0x251/0x310 kernel/task_work.c:227
 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:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fced298f497
Code: a8 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 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fff78f97c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fced2a10854 RCX: 00007fced298f497
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff78f97d20
RBP: 00007fff78f97d20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff78f98db0
R13: 00007fced2a10854 R14: 000000000001b234 R15: 00007fff78f98df0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:generic_shutdown_super+0x2ca/0x2d0 fs/super.c:650
Code: 1b 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 79 bc ed ff 48 8b 13 48 c7 c7 20 e2 58 8c 4c 89 e6 e8 97 5a ea fe 90 <0f> 0b 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003fdfd10 EFLAGS: 00010246
RAX: 000000000000002f RBX: ffffffff8f2aeec0 RCX: 096803ea5bee1400
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 1ffff1100a8d1cf0 R08: ffffffff81a21cac R09: 1ffff920007fbf3c
R10: dffffc0000000000 R11: fffff520007fbf3d R12: ffff88805468e668
R13: dffffc0000000000 R14: ffffffff8c8c4c98 R15: ffff88805468e780
FS:  000055555dc2a500(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ba3cba3318 CR3: 000000006e726000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400