BTRFS warning (device loop9): qgroup 0/5 has unreleased space, type 0 rsv 40960 BTRFS error (device loop9): qgroup reserved space leaked BTRFS info (device loop9): at unmount dio bytes count 40960 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 6992 at fs/btrfs/block-group.c:159 btrfs_put_block_group+0x2fb/0x350 fs/btrfs/block-group.c:159 Modules linked in: CPU: 0 UID: 0 PID: 6992 Comm: syz-executor Not tainted 6.16.0-rc4-syzkaller-00108-g17bbde2e1716 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:btrfs_put_block_group+0x2fb/0x350 fs/btrfs/block-group.c:159 Code: 42 80 3c 20 00 74 08 48 89 df e8 80 04 3d fe bf 50 17 00 00 48 03 3b 48 89 de e8 10 83 01 00 e9 c0 fe ff ff e8 56 ac db fd 90 <0f> 0b 90 e9 84 fe ff ff e8 48 ac db fd e9 7a fe ff ff e8 3e ac db RSP: 0018:ffffc9000550fac0 EFLAGS: 00010293 RAX: ffffffff83e4a13a RBX: ffff888034365800 RCX: ffff8880767abc00 RDX: 0000000000000000 RSI: 000000000000a000 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffff888057751b67 R09: 1ffff1100aeea36c R10: dffffc0000000000 R11: ffffed100aeea36d R12: dffffc0000000000 R13: ffff888034365b18 R14: 000000000000a000 R15: dffffc0000000000 FS: 00005555845f7500(0000) GS:ffff888125c84000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc791b65d8 CR3: 000000007cb7c000 CR4: 00000000003526f0 Call Trace: btrfs_free_block_groups+0xb6b/0xf40 fs/btrfs/block-group.c:4551 close_ctree+0x7f0/0xd60 fs/btrfs/disk-io.c:4426 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 kill_anon_super+0x3b/0x70 fs/super.c:1282 btrfs_kill_super+0x41/0x50 fs/btrfs/super.c:2095 deactivate_locked_super+0xb9/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd748f8fc57 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:00007ffcdd806688 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fd749010925 RCX: 00007fd748f8fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcdd806740 RBP: 00007ffcdd806740 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcdd8077d0 R13: 00007fd749010925 R14: 000000000002f6af R15: 00007ffcdd807810