------------[ cut here ]------------
WARNING: CPU: 0 PID: 6009 at fs/bcachefs/fs-io.c:361 __bch2_truncate_folio+0x179c/0x1a30 fs/bcachefs/fs-io.c:361
Modules linked in:
CPU: 0 UID: 0 PID: 6009 Comm: syz.1.18 Not tainted 6.16.0-syzkaller-11895-gcca7a0aae895-dirty #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 fs/bcachefs/fs-io.c:361
Code: 5f 5d e9 57 4b 3c 07 cc e8 21 7b 80 fd 48 c7 c7 2a 55 a3 8d e8 85 61 e9 ff 89 05 5f 1e 86 15 e9 49 ea ff ff e8 05 7b 80 fd 90 <0f> 0b 90 e9 26 f9 ff ff e8 37 66 39 07 e8 f2 7a 80 fd be 00 10 00
RSP: 0018:ffffc900029bf9e0 EFLAGS: 00010293
RAX: ffffffff843f30ab RBX: 0000000000000000 RCX: ffff888021970000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900029bfbb0 R08: ffffea0000fa5ac7 R09: 1ffffd40001f4b58
R10: dffffc0000000000 R11: fffff940001f4b59 R12: 1ffff11007fae0fd
R13: dffffc0000000000 R14: ffff88803fd707e8 R15: 0000000000000000
FS:  00007f6eb8ff66c0(0000) GS:ffff8880b8624000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31163fff CR3: 000000010c678000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 bch2_truncate_folios fs/bcachefs/fs-io.c:400 [inline]
 bchfs_fallocate+0x233/0x680 fs/bcachefs/fs-io.c:777
 bch2_fallocate_dispatch+0x28a/0x410 fs/bcachefs/fs-io.c:836
 vfs_fallocate+0x669/0x7e0 fs/open.c:342
 ksys_fallocate fs/open.c:366 [inline]
 __do_sys_fallocate fs/open.c:371 [inline]
 __se_sys_fallocate fs/open.c:369 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:369
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6eb998ebe9
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:00007f6eb8ff6038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f6eb9bb5fa0 RCX: 00007f6eb998ebe9
RDX: 0000000000000003 RSI: 0000000000000010 RDI: 0000000000000004
RBP: 00007f6eb9a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000007c27 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6eb9bb6038 R14: 00007f6eb9bb5fa0 R15: 00007ffed2f33658
 </TASK>
