VFS: Busy inodes after unmount of loop0 (btrfs)
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kernel BUG at fs/super.c:502!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 4997 Comm: syz-executor126 Not tainted 6.4.0-rc2-syzkaller-00163-g2d1bcbc6cd70 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
RIP: 0010:generic_shutdown_super+0x3bb/0x480 fs/super.c:502
Code: 6b 28 48 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 c4 00 00 00 48 8b 55 00 48 8d b3 a8 06 00 00 48 c7 c7 20 ca 5b 8a e8 d5 99 81 ff <0f> 0b e8 3e 7d f0 ff e9 6a fc ff ff e8 34 7d f0 ff e9 f1 fd ff ff
RSP: 0018:ffffc900039afd58 EFLAGS: 00010282
RAX: 000000000000002f RBX: ffff888022c9c000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168b8fc RDI: 0000000000000005
RBP: ffffffff8ce8c1e0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000001 R12: ffff888022c9c7d8
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880187456c0
FS:  0000555555f2e300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f89803b68e5 CR3: 0000000075cde000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 kill_anon_super+0x3a/0x60 fs/super.c:1107
 btrfs_kill_super+0x3c/0x50 fs/btrfs/super.c:2138
 deactivate_locked_super+0x98/0x160 fs/super.c:331
 deactivate_super+0xb1/0xd0 fs/super.c:362
 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1177
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 ptrace_notify+0x118/0x140 kernel/signal.c:2369
 ptrace_report_syscall include/linux/ptrace.h:411 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]
 syscall_exit_work kernel/entry/common.c:252 [inline]
 syscall_exit_to_user_mode_prepare+0x129/0x220 kernel/entry/common.c:279
 __syscall_exit_to_user_mode_work kernel/entry/common.c:284 [inline]
 syscall_exit_to_user_mode+0xd/0x50 kernel/entry/common.c:297
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f24e2be0d27
Code: 07 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc4968b128 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 000000000000b4bb RCX: 00007f24e2be0d27
RDX: 00007ffc4968b1e8 RSI: 000000000000000a RDI: 00007ffc4968b1e0
RBP: 00007ffc4968b1e0 R08: 00000000ffffffff R09: 00007ffc4968afc0
R10: 0000555555f2f633 R11: 0000000000000206 R12: 00007ffc4968c250
R13: 0000555555f2f5f0 R14: 00007ffc4968b150 R15: 0000000000000010
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:generic_shutdown_super+0x3bb/0x480 fs/super.c:502
Code: 6b 28 48 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 c4 00 00 00 48 8b 55 00 48 8d b3 a8 06 00 00 48 c7 c7 20 ca 5b 8a e8 d5 99 81 ff <0f> 0b e8 3e 7d f0 ff e9 6a fc ff ff e8 34 7d f0 ff e9 f1 fd ff ff
RSP: 0018:ffffc900039afd58 EFLAGS: 00010282
RAX: 000000000000002f RBX: ffff888022c9c000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168b8fc RDI: 0000000000000005
RBP: ffffffff8ce8c1e0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000001 R12: ffff888022c9c7d8
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880187456c0
FS:  0000555555f2e300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f89803b68e5 CR3: 0000000075cde000 CR4: 0000000000350ef0