BTRFS info (device loop0): at unmount dio bytes count 45056 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 4938 at fs/btrfs/block-group.c:142 btrfs_put_block_group+0x269/0x280 fs/btrfs/block-group.c:142 Modules linked in: CPU: 0 PID: 4938 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:btrfs_put_block_group+0x269/0x280 fs/btrfs/block-group.c:142 Code: bd a5 59 fe bf c8 15 00 00 48 03 3b 48 89 de e8 6d 4d 01 00 e9 4a ff ff ff e8 e3 99 14 fe 0f 0b e9 6a ff ff ff e8 d7 99 14 fe <0f> 0b e9 04 ff ff ff e8 cb 99 14 fe e9 fa fe ff ff 66 0f 1f 44 00 RSP: 0018:ffffc90002fbfc18 EFLAGS: 00010293 RAX: ffffffff836486f9 RBX: ffff88807f661800 RCX: ffff888028778000 RDX: 0000000000000000 RSI: 000000000000b000 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffff88805c3a19d7 R09: 1ffff1100b87433a R10: dffffc0000000000 R11: ffffed100b87433b R12: ffff88807f661b10 R13: ffff88807f661800 R14: 000000000000b000 R15: dffffc0000000000 FS: 000055555751d500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f99da988e9c CR3: 0000000022e9a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: btrfs_free_block_groups+0x803/0xcc0 fs/btrfs/block-group.c:3982 close_ctree+0x72c/0x8e0 fs/btrfs/disk-io.c:4528 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_anon_super+0x36/0x70 fs/super.c:1089 btrfs_kill_super+0x3d/0x50 fs/btrfs/super.c:2390 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f76b3e795d7 Code: a2 c7 05 bc 6f 21 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 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 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffc1a596df8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f76b3f0b1c3 RCX: 00007f76b3e795d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc1a596eb0 RBP: 00007ffc1a596eb0 R08: 00007ffc1a597eb0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc1a597f40 R13: 00007f76b3f0b1c3 R14: 00000000000208bf R15: 00007ffc1a597f80