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 -98304 free, is not full BTRFS info (device loop0): space_info total=4194304, used=4096, pinned=0, reserved=0, may_use=98304, readonly=4190208 zone_unusable=0 BTRFS info (device loop0): global_block_rsv: size 1441792 reserved 1441792 BTRFS info (device loop0): trans_block_rsv: size 0 reserved 0 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 32768 reserved 32768 BTRFS info (device loop0): delayed_refs_rsv: size 1507328 reserved 1429504 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) [readonly] 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/u4:0/12 WARNING: fs/btrfs/block-group.c:4203 at btrfs_chunk_alloc+0x10cc/0x1330 fs/btrfs/block-group.c:4444, CPU#0: kworker/u4:0/12 Modules linked in: CPU: 0 UID: 0 PID: 12 Comm: kworker/u4:0 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_data_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 4d 5b fc fd e9 dc ef ff ff e8 83 30 8d fd eb 10 e8 7c 30 8d fd eb 09 e8 75 30 8d 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:ffffc9000025f7d8 EFLAGS: 00010293 RAX: ffffffff8439e15b RBX: 1ffff11003f52c16 RCX: ffff88801cedca80 RDX: 0000000000000000 RSI: ffffffff8f1fcb40 RDI: 00000000ffffffe4 RBP: ffff8880529e0001 R08: ffff88801cedca80 R09: 0000000000000003 R10: 00000000fffffffb R11: 0000000000000000 R12: 1ffff11003f52c16 R13: 00000000ffffffe4 R14: ffffffffffffffe4 R15: ffff888050f36180 FS: 0000000000000000(0000) GS:ffff88808c545000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fea037ff000 CR3: 000000001d0c8000 CR4: 0000000000352ef0 Call Trace: flush_space+0x3df/0xde0 fs/btrfs/space-info.c:908 do_async_reclaim_data_space+0x137/0x550 fs/btrfs/space-info.c:1455 btrfs_async_reclaim_data_space+0x41/0x90 fs/btrfs/space-info.c:1519 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 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