------------[ cut here ]------------ WARNING: fs/btrfs/extent-tree.c:3228 at __btrfs_free_extent+0x15b4/0x3f40 fs/btrfs/extent-tree.c:3228, CPU#0: kworker/u4:13/2778 Modules linked in: CPU: 0 UID: 0 PID: 2778 Comm: kworker/u4:13 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_metadata_space RIP: 0010:__btrfs_free_extent+0x15b4/0x3f40 fs/btrfs/extent-tree.c:3228 Code: fd eb 12 e8 be 88 d9 fd 84 c0 0f 84 55 02 00 00 e8 41 af f3 fd 48 8b 5c 24 18 48 8b 44 24 50 4c 8b 74 24 08 e9 d8 0b 00 00 90 <0f> 0b 90 48 8b 44 24 20 42 80 3c 28 00 74 0a 48 8b 7c 24 08 e8 c3 RSP: 0018:ffffc90002c3f260 EFLAGS: 00010246 RAX: 0000000000000002 RBX: ffff888042a25bf0 RCX: 0000000000000005 RDX: ffffffff83ce01ec RSI: ffffffff8e6f8a00 RDI: 00000000fffffffe RBP: ffffc90002c3f410 R08: ffff8880385e0000 R09: 0000000000000002 R10: 00000000fffffffe R11: 0000000000000000 R12: 00000000fffffffe R13: dffffc0000000000 R14: 00000000fffffffe R15: ffff888043c07d10 FS: 0000000000000000(0000) GS:ffff88808d22a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbc751e70a0 CR3: 000000001234e000 CR4: 0000000000352ef0 Call Trace: run_one_delayed_ref fs/btrfs/extent-tree.c:-1 [inline] btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1973 [inline] __btrfs_run_delayed_refs+0xe6a/0x3af0 fs/btrfs/extent-tree.c:2048 btrfs_run_delayed_refs+0xe6/0x3a0 fs/btrfs/extent-tree.c:2160 flush_space+0x28f/0xd20 fs/btrfs/space-info.c:-1 do_async_reclaim_metadata_space+0x11e/0x350 fs/btrfs/space-info.c:1185 btrfs_async_reclaim_metadata_space+0x89/0xe0 fs/btrfs/space-info.c:1252 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