BTRFS error (device loop3): failed to run delayed ref for logical 5373952 num_bytes 65536 type 178 action 1 ref_mod 1: -2 ------------[ cut here ]------------ BTRFS: Transaction aborted (error -2) WARNING: fs/btrfs/extent-tree.c:2247 at btrfs_run_delayed_refs+0x340/0x3c0 fs/btrfs/extent-tree.c:2247, CPU#1: syz-executor/5833 Modules linked in: CPU: 1 UID: 0 PID: 5833 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:btrfs_run_delayed_refs+0x342/0x3c0 fs/btrfs/extent-tree.c:2247 Code: 31 db e8 61 40 db fd 89 d8 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f e9 b7 aa e2 fc e8 47 40 db fd 48 8d 3d 40 28 b5 0c 89 de <67> 48 0f b9 3a 41 bc 01 00 00 00 e8 2e 40 db fd 45 89 e0 89 d9 ba RSP: 0018:ffffc900015f7b28 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 00000000fffffffe RCX: ffffffff842d9541 RDX: ffff888034a9bd00 RSI: 00000000fffffffe RDI: ffffffff90e2bea0 RBP: ffff888077b13000 R08: 0000000000000005 R09: fffffffffffffffb R10: fffffffffffffffe R11: 0000000000000000 R12: ffff888054321c00 R13: ffff888055e1c000 R14: ffffed100abc386b R15: ffff888077b13060 FS: 0000555556463500(0000) GS:ffff88812443c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c44f977 CR3: 000000005b85f000 CR4: 0000000000350ef0 Call Trace: btrfs_commit_transaction+0x1f4d/0x3860 fs/btrfs/transaction.c:2254 btrfs_sync_fs+0x129/0x7e0 fs/btrfs/super.c:1051 sync_filesystem fs/sync.c:66 [inline] sync_filesystem+0x1d0/0x290 fs/sync.c:30 generic_shutdown_super+0x86/0x360 fs/super.c:625 kill_anon_super+0x3a/0x60 fs/super.c:1292 btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2127 deactivate_locked_super+0xc1/0x1b0 fs/super.c:476 deactivate_super fs/super.c:509 [inline] deactivate_super+0xe7/0x110 fs/super.c:505 cleanup_mnt+0x21f/0x450 fs/namespace.c:1312 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f771d99d9d7 Code: a2 c7 05 1c fd 24 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:00007ffebb2e86d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f771da32050 RCX: 00007f771d99d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffebb2e8790 RBP: 00007ffebb2e8790 R08: 00007ffebb2e9790 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffebb2e9820 R13: 00007f771da32050 R14: 000000000001a839 R15: 00007ffebb2e9860 ---------------- Code disassembly (best guess): 0: 31 db xor %ebx,%ebx 2: e8 61 40 db fd call 0xfddb4068 7: 89 d8 mov %ebx,%eax 9: 48 83 c4 08 add $0x8,%rsp d: 5b pop %rbx e: 5d pop %rbp f: 41 5c pop %r12 11: 41 5d pop %r13 13: 41 5e pop %r14 15: 41 5f pop %r15 17: e9 b7 aa e2 fc jmp 0xfce2aad3 1c: e8 47 40 db fd call 0xfddb4068 21: 48 8d 3d 40 28 b5 0c lea 0xcb52840(%rip),%rdi # 0xcb52868 28: 89 de mov %ebx,%esi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 41 bc 01 00 00 00 mov $0x1,%r12d 35: e8 2e 40 db fd call 0xfddb4068 3a: 45 89 e0 mov %r12d,%r8d 3d: 89 d9 mov %ebx,%ecx 3f: ba .byte 0xba