btree ptr not marked in member info btree allocated bitmap
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 7589ab5e0c11cc7a written 24 min_key POS_MIN durability: 1 ptr: 0:38:0 gen 0, fixing
btree ptr not marked in member info btree allocated bitmap
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 9aa2895aefce4bdf written 24 min_key POS_MIN durability: 1 ptr: 0:41:0 gen 0, fixing
btree ptr not marked in member info btree allocated bitmap
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq c0bef60d07ceb940 written 16 min_key POS_MIN durability: 1 ptr: 0:35:0 gen 0, fixing
btree ptr not marked in member info btree allocated bitmap
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq ebb8d5a9e3463bdb written 16 min_key POS_MIN durability: 1 ptr: 0:32:0 gen 0, fixing
btree ptr not marked in member info btree allocated bitmap
  u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq e81e1ed936acf3df written 0 min_key POS_MIN durability: 1 ptr: 0:29:0 gen 0, fixing
bucket 0:29 data type btree ptr gen 0 missing in alloc btree
while marking u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq e81e1ed936acf3df written 0 min_key POS_MIN durability: 1 ptr: 0:29:0 gen 0, fixing
bucket 0:29 gen 0 has wrong data_type: got free, should be btree, fixing
bucket 0:29 gen 0 data type btree has wrong dirty_sectors: got 0, should be 256, fixing
 done
bcachefs (loop0): going read-write
bcachefs (loop0): journal_replay... done
bcachefs (loop0): check_inodes... done
bcachefs (loop0): resume_logged_ops... done
bcachefs (loop0): delete_dead_inodes... done
bcachefs (loop0): Fixed errors, running fsck a second time to verify fs is clean
bcachefs (loop0): check_inodes... done
bcachefs (loop0): resume_logged_ops... done
bcachefs (loop0): delete_dead_inodes... done
bcachefs (loop0): done starting filesystem
bcachefs (loop0): non free bucket in freespace btree
  freespace key u64s 5 type set 0:29:0 len 2 ver 0
  u64s 12 type alloc_v4 0:27:0 len 0 ver 0: 
  gen 0 oldest_gen 0 data_type btree
  journal_seq       4
  need_discard      1
  need_inc_gen      1
  dirty_sectors     256
  stripe_sectors    0
  cached_sectors    0
  stripe            0
  stripe_redundancy 0
  io_time[READ]     1
  io_time[WRITE]    256
  fragmentation     0
  bp_start          8
2 transaction updates for bch2_truncate journal seq 0
  update: btree=logged_ops cached=0 __bch2_logged_op_start fs/bcachefs/logged_ops.c:85 [inline]
  update: btree=logged_ops cached=0 bch2_logged_op_start+0x181/0x310 fs/bcachefs/logged_ops.c:92
    old u64s 5 type deleted 0:1:0 len 0 ver 0
    new u64s 8 type logged_op_truncate 0:1:0 len 0 ver 0: subvol=1 inum=536870913 new_i_size=0
  update: btree=logged_ops cached=1 __bch2_logged_op_start fs/bcachefs/logged_ops.c:85 [inline]
  update: btree=logged_ops cached=1 bch2_logged_op_start+0x181/0x310 fs/bcachefs/logged_ops.c:92
    old u64s 5 type deleted 0:1:0 len 0 ver 0
    new u64s 8 type logged_op_truncate 0:1:0 len 0 ver 0: subvol=1 inum=536870913 new_i_size=0
bcachefs (loop0): bch2_btree_update_start(): error EIO
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5322 at fs/bcachefs/fs-io.c:315 __bch2_truncate_folio+0x22aa/0x26b0 fs/bcachefs/fs-io.c:315
Modules linked in:
CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted 6.13.0-rc5-syzkaller-00161-g63676eefb7a0 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__bch2_truncate_folio+0x22aa/0x26b0 fs/bcachefs/fs-io.c:315
Code: 41 5f 5d c3 cc cc cc cc e8 73 b1 67 fd 48 c7 c7 4a 5a 11 8e e8 17 8b e8 ff 89 05 01 32 1d 16 e9 2c e0 ff ff e8 57 b1 67 fd 90 <0f> 0b 90 e9 88 f8 ff ff 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c ff
RSP: 0018:ffffc9000d497920 EFLAGS: 00010283
RAX: ffffffff8437d2c9 RBX: 0000000000000000 RCX: 0000000000100000
RDX: ffffc9000e45a000 RSI: 00000000000013e5 RDI: 00000000000013e6
RBP: ffffc9000d497c10 R08: ffffffff8437cb4c R09: 1ffffd40002930a0
R10: dffffc0000000000 R11: fffff940002930a1 R12: 1ffff110087e03ca
R13: ffffc9000d497ba0 R14: ffff888043f01e50 R15: 0000000000000000
FS:  00007facf92676c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007facecfff000 CR3: 00000000403f0000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bch2_truncate_folios fs/bcachefs/fs-io.c:354 [inline]
 bchfs_fallocate+0x219/0x730 fs/bcachefs/fs-io.c:721
 bch2_fallocate_dispatch+0x3ac/0x540 fs/bcachefs/fs-io.c:780
 vfs_fallocate+0x569/0x6e0 fs/open.c:327
 ksys_fallocate fs/open.c:351 [inline]
 __do_sys_fallocate fs/open.c:356 [inline]
 __se_sys_fallocate fs/open.c:354 [inline]
 __x64_sys_fallocate+0xbc/0x110 fs/open.c:354
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7facf8385d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007facf9267038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007facf8575fa0 RCX: 00007facf8385d29
RDX: 0000000000000004 RSI: 0000000000000010 RDI: 0000000000000008
RBP: 00007facf8401b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007facf8575fa0 R15: 00007ffdd366d5f8
 </TASK>