BTRFS error (device loop0): allocation failed flags 10, wanted 4096 tree-log 0, relocation: 0 BTRFS info (device loop0): space_info SYSTEM (sub-group id 0) has 4091904 free, is not full BTRFS info (device loop0): space_info total=4194304, used=4096, pinned=0, reserved=0, may_use=98304, readonly=0 zone_unusable=0 BTRFS info (device loop0): global_block_rsv: size 1441792 reserved 1441792 BTRFS info (device loop0): trans_block_rsv: size 786432 reserved 778240 BTRFS info (device loop0): chunk_block_rsv: size 98304 reserved 94208 BTRFS info (device loop0): remap_block_rsv: size 0 reserved 0 BTRFS info (device loop0): delayed_block_rsv: size 0 reserved 0 BTRFS info (device loop0): delayed_refs_rsv: size 589824 reserved 524288 BTRFS info (device loop0): block group 1048576 has 4194304 bytes, 4096 used 0 pinned 0 reserved 0 delalloc 0 super 0 zone_unusable (4190208 bytes available) BTRFS info (device loop0): block group has cluster?: no BTRFS info (device loop0): 0 free space entries at or bigger than 4096 bytes BTRFS info (device loop0): 4190208 bytes available across all block groups ------------[ cut here ]------------ btrfs_abort_should_print_stack(__error) WARNING: fs/btrfs/block-group.c:4203 at do_chunk_alloc fs/btrfs/block-group.c:4203 [inline], CPU#0: kworker/u4:2/24 WARNING: fs/btrfs/block-group.c:4203 at btrfs_chunk_alloc+0x10cc/0x1330 fs/btrfs/block-group.c:4444, CPU#0: kworker/u4:2/24 Modules linked in: CPU: 0 UID: 0 PID: 24 Comm: kworker/u4:2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: events_unbound btrfs_async_reclaim_metadata_space RIP: 0010:do_chunk_alloc fs/btrfs/block-group.c:4203 [inline] RIP: 0010:btrfs_chunk_alloc+0x10cc/0x1330 fs/btrfs/block-group.c:4444 Code: 07 38 c1 0f 8c e9 ef ff ff 48 89 df e8 9d 4e fc fd e9 dc ef ff ff e8 d3 6e 8b fd eb 10 e8 cc 6e 8b fd eb 09 e8 c5 6e 8b fd 90 <0f> 0b 90 44 89 f1 f7 d9 e9 38 fd ff ff 48 8b 4c 24 08 48 83 c1 5b RSP: 0018:ffffc9000031f6f8 EFLAGS: 00010293 RAX: ffffffff843ba0cb RBX: 1ffff110086a7b16 RCX: ffff88801bf9cb00 RDX: 0000000000000000 RSI: ffffffff8f203b80 RDI: 00000000ffffffe4 RBP: ffff88800011c001 R08: ffff88801bf9cb00 R09: 0000000000000003 R10: 00000000fffffffb R11: 0000000000000000 R12: 1ffff110086a7b16 R13: 00000000ffffffe4 R14: ffffffffffffffe4 R15: ffff888012f5a180 FS: 0000000000000000(0000) GS:ffff88808c519000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7cc372a000 CR3: 00000000128ad000 CR4: 0000000000352ef0 Call Trace: flush_space+0x3df/0xde0 fs/btrfs/space-info.c:908 do_async_reclaim_metadata_space+0x3e8/0x940 fs/btrfs/space-info.c:1211 btrfs_async_reclaim_metadata_space+0x89/0xe0 fs/btrfs/space-info.c:1278 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245