------------[ cut here ]------------
WARNING: fs/bcachefs/fs-io.c:361 at __bch2_truncate_folio+0x179c/0x1a30, CPU#1: syz.1.276/8477
Modules linked in:
CPU: 1 UID: 0 PID: 8477 Comm: syz.1.276 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__bch2_truncate_folio+0x179c/0x1a30
Code: 5f 5d c3 cc cc cc cc cc e8 41 0b 7e fd 48 c7 c7 58 d3 c3 8d e8 95 49 e9 ff 89 05 6f bb a8 15 e9 49 ea ff ff e8 25 0b 7e fd 90 <0f> 0b 90 e9 26 f9 ff ff e8 77 f1 3f 07 e8 12 0b 7e fd be 00 10 00
RSP: 0018:ffffc90002bf7560 EFLAGS: 00010287
RAX: ffffffff84419f5b RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9002292a000 RSI: 00000000000016ed RDI: 00000000000016ee
RBP: ffffc90002bf7730 R08: ffffea00049cb807 R09: 1ffffd4000939700
R10: dffffc0000000000 R11: fffff94000939701 R12: 1ffff11022aa6883
R13: dffffc0000000000 R14: ffff888115534418 R15: 0000000000000000
FS:  00007f4e350646c0(0000) GS:ffff8881a39f1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c24001d CR3: 000000003b55c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 bchfs_fpunch+0x10f/0x520
 bch2_fallocate_dispatch+0x2bc/0x410
 vfs_fallocate+0x669/0x7e0
 file_ioctl+0x611/0x780
 do_vfs_ioctl+0xb33/0x1430
 __se_sys_ioctl+0x82/0x170
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4e3418ebe9
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:00007f4e35064038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4e343c5fa0 RCX: 00007f4e3418ebe9
RDX: 0000200000000100 RSI: 0000000040305829 RDI: 0000000000000004
RBP: 00007f4e34211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4e343c6038 R14: 00007f4e343c5fa0 R15: 00007ffd8f767778
 </TASK>
