BTRFS error (device loop0): allocation failed flags 2, 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 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 327680 reserved 262144 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: Transaction aborted (error -28) WARNING: fs/btrfs/block-group.c:4182 at do_chunk_alloc fs/btrfs/block-group.c:4182 [inline], CPU#0: kworker/u4:2/25 WARNING: fs/btrfs/block-group.c:4182 at btrfs_chunk_alloc+0x101d/0x15e0 fs/btrfs/block-group.c:4423, CPU#0: kworker/u4:2/25 Modules linked in: CPU: 0 UID: 0 PID: 25 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:4182 [inline] RIP: 0010:btrfs_chunk_alloc+0x101f/0x15e0 fs/btrfs/block-group.c:4423 Code: 07 33 ae fd e9 6d 01 00 00 e8 0d 3f 93 fd 84 c0 74 22 e8 f4 32 ae fd e9 5a 01 00 00 e8 ea 32 ae fd 48 8d 3d 03 f5 22 0c 89 de <67> 48 0f b9 3a e9 b3 fc ff ff e8 c2 52 92 07 41 89 c6 31 ff 89 c6 RSP: 0018:ffffc900003376d0 EFLAGS: 00010293 RAX: ffffffff841787b6 RBX: ffffffffffffffe4 RCX: ffff88801ebd8000 RDX: 0000000000000000 RSI: 00000000ffffffe4 RDI: ffffffff903a7cc0 RBP: 0000000000000000 R08: ffff88801ebd8000 R09: 0000000000000003 R10: 00000000fffffffb R11: 0000000000000000 R12: 1ffff11007929016 R13: ffff88801fcf94f0 R14: ffff8880427a4001 R15: ffff888040fa5000 FS: 0000000000000000(0000) GS:ffff88808c888000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007effbb6f6000 CR3: 00000000122f1000 CR4: 0000000000352ef0 Call Trace: flush_space+0x3fb/0xe20 fs/btrfs/space-info.c:908 do_async_reclaim_metadata_space+0x3fc/0x960 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:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 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 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 33 ae fd e9 6d 01 xor 0x16de9fd(%rsi),%ebp 6: 00 00 add %al,(%rax) 8: e8 0d 3f 93 fd call 0xfd933f1a d: 84 c0 test %al,%al f: 74 22 je 0x33 11: e8 f4 32 ae fd call 0xfdae330a 16: e9 5a 01 00 00 jmp 0x175 1b: e8 ea 32 ae fd call 0xfdae330a 20: 48 8d 3d 03 f5 22 0c lea 0xc22f503(%rip),%rdi # 0xc22f52a 27: 89 de mov %ebx,%esi * 29: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2e: e9 b3 fc ff ff jmp 0xfffffce6 33: e8 c2 52 92 07 call 0x79252fa 38: 41 89 c6 mov %eax,%r14d 3b: 31 ff xor %edi,%edi 3d: 89 c6 mov %eax,%esi