syzbot

loop0: detected capacity change from 0 to 64
------------[ cut here ]------------
WARNING: CPU: 1 PID: 6091 at fs/buffer.c:1183 mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1183
Modules linked in:
CPU: 1 UID: 0 PID: 6091 Comm: syz.0.27 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1183
Code: 4c 89 f7 e8 a9 9b e1 ff 49 8b 3e be 40 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 14 e9 fb ff e8 bf dc 7f ff eb 8c e8 b8 dc 7f ff 90 <0f> 0b 90 e9 95 fd ff ff e8 aa dc 7f ff 90 0f 0b 90 e9 bf fd ff ff
RSP: 0018:ffffc90003d7f608 EFLAGS: 00010293
RAX: ffffffff823ed098 RBX: ffff888041d62de0 RCX: ffff88802038bc00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888036e34001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10083ac5bd R12: ffff888047042c00
R13: ffff888041d62a68 R14: ffff888041d62de0 R15: 000000000000000a
FS:  0000555569a76500(0000) GS:ffff888126ef6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff9bcf3f68c CR3: 0000000038082000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 bfs_move_block fs/bfs/file.c:44 [inline]
 bfs_move_blocks fs/bfs/file.c:57 [inline]
 bfs_get_block+0x5da/0xae0 fs/bfs/file.c:126
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
 block_write_begin+0x8a/0x120 fs/buffer.c:2256
 bfs_write_begin+0x35/0xd0 fs/bfs/file.c:180
 generic_perform_write+0x29d/0x8c0 mm/filemap.c:4254
 generic_file_write_iter+0x118/0x550 mm/filemap.c:4397
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5d5/0xb40 fs/read_write.c:686
 ksys_pwrite64 fs/read_write.c:793 [inline]
 __do_sys_pwrite64 fs/read_write.c:801 [inline]
 __se_sys_pwrite64 fs/read_write.c:798 [inline]
 __x64_sys_pwrite64+0x196/0x220 fs/read_write.c:798
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faa82b9f749
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:00007ffde23b5f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007faa82df5fa0 RCX: 00007faa82b9f749
RDX: 000000000000fdef RSI: 0000200000000140 RDI: 0000000000000006
RBP: 00007faa82c23f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000e7c R11: 0000000000000246 R12: 0000000000000000
R13: 00007faa82df5fa0 R14: 00007faa82df5fa0 R15: 0000000000000004
 </TASK>