BTRFS info (device loop6): last unmount of filesystem 395ef67a-297e-477c-816d-cd80a5b93e5d BTRFS info (device loop6): at unmount dio bytes count 32768 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 6171 at fs/btrfs/block-group.c:159 btrfs_put_block_group+0x2fb/0x350 fs/btrfs/block-group.c:159 Modules linked in: CPU: 1 UID: 0 PID: 6171 Comm: syz-executor Not tainted 6.16.0-rc4-syzkaller-00123-g4c06e63b9203 #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 e0 e5 3c fe bf 50 17 00 00 48 03 3b 48 89 de e8 10 83 01 00 e9 c0 fe ff ff e8 b6 8d db fd 90 <0f> 0b 90 e9 84 fe ff ff e8 a8 8d db fd e9 7a fe ff ff e8 9e 8d db RSP: 0018:ffffc90004c77ac0 EFLAGS: 00010293 RAX: ffffffff83e4cfda RBX: ffff888055a74000 RCX: ffff8880275c8000 RDX: 0000000000000000 RSI: 0000000000008000 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffff8880530adb67 R09: 1ffff1100a615b6c R10: dffffc0000000000 R11: ffffed100a615b6d R12: dffffc0000000000 R13: ffff888055a74318 R14: 0000000000008000 R15: dffffc0000000000 FS: 0000555559c75500(0000) GS:ffff888125d51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056505109e660 CR3: 0000000075dbe000 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: 0033:0x7ff6b138fc57 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:00007fff82fb2648 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007ff6b1410925 RCX: 00007ff6b138fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff82fb2700 RBP: 00007fff82fb2700 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff82fb3790 R13: 00007ff6b1410925 R14: 000000000002de5e R15: 00007fff82fb37d0