BTRFS error (device loop0): failed to run delayed ref for logical 10035200 num_bytes 4096 type 176 action 1 ref_mod 1: -28 ------------[ cut here ]------------ BTRFS: Transaction aborted (error -28) WARNING: fs/btrfs/extent-tree.c:2162 at btrfs_run_delayed_refs+0x30b/0x3a0 fs/btrfs/extent-tree.c:2162, CPU#0: kworker/u4:11/2661 Modules linked in: CPU: 0 UID: 0 PID: 2661 Comm: kworker/u4:11 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: events_unbound btrfs_async_reclaim_data_space RIP: 0010:btrfs_run_delayed_refs+0x30e/0x3a0 fs/btrfs/extent-tree.c:2162 Code: 85 e4 75 07 e8 f3 4b f5 fd eb 7a e8 8c 25 db fd 84 c0 74 20 e8 e3 4b f5 fd eb 6a e8 dc 4b f5 fd 48 8d 3d 05 90 de 0b 44 89 fe <67> 48 0f b9 3a e9 0b ff ff ff e8 83 43 91 07 41 89 c4 31 ff 89 c6 RSP: 0018:ffffc9000fe67498 EFLAGS: 00010293 RAX: ffffffff83cc74c4 RBX: ffff88804e513a68 RCX: ffff888000fb4980 RDX: 0000000000000000 RSI: 00000000ffffffe4 RDI: ffffffff8fab04d0 RBP: 0000000000000000 R08: ffff888000fb4980 R09: 0000000000000003 R10: 00000000fffffffb R11: 0000000000000000 R12: ffff888000efc001 R13: ffff88801269c000 R14: dffffc0000000000 R15: 00000000ffffffe4 FS: 0000000000000000(0000) GS:ffff88808d22a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f28ba5bd000 CR3: 0000000042925000 CR4: 0000000000352ef0 Call Trace: btrfs_commit_transaction+0x28b/0x3b10 fs/btrfs/transaction.c:2229 flush_space+0x4dd/0xd20 fs/btrfs/space-info.c:921 do_async_reclaim_data_space+0x29a/0x520 fs/btrfs/space-info.c:1437 btrfs_async_reclaim_data_space+0x41/0x90 fs/btrfs/space-info.c:1485 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 ---------------- Code disassembly (best guess): 0: 85 e4 test %esp,%esp 2: 75 07 jne 0xb 4: e8 f3 4b f5 fd call 0xfdf54bfc 9: eb 7a jmp 0x85 b: e8 8c 25 db fd call 0xfddb259c 10: 84 c0 test %al,%al 12: 74 20 je 0x34 14: e8 e3 4b f5 fd call 0xfdf54bfc 19: eb 6a jmp 0x85 1b: e8 dc 4b f5 fd call 0xfdf54bfc 20: 48 8d 3d 05 90 de 0b lea 0xbde9005(%rip),%rdi # 0xbde902c 27: 44 89 fe mov %r15d,%esi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: e9 0b ff ff ff jmp 0xffffff3f 34: e8 83 43 91 07 call 0x79143bc 39: 41 89 c4 mov %eax,%r12d 3c: 31 ff xor %edi,%edi 3e: 89 c6 mov %eax,%esi