loop2: detected capacity change from 0 to 64
------------[ cut here ]------------
WARNING: CPU: 0 PID: 8389 at fs/buffer.c:1186 mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1186
Modules linked in:
CPU: 0 UID: 0 PID: 8389 Comm: syz.2.694 Not tainted 6.15.0-rc4-syzkaller-00040-g8bac8898fe39 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1186
Code: 4c 89 f7 e8 79 0d de ff 49 8b 3e be 20 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 c4 34 fc ff e8 5f 18 7c ff eb 8c e8 58 18 7c ff 90 <0f> 0b 90 e9 95 fd ff ff e8 4a 18 7c ff 90 0f 0b 90 e9 bf fd ff ff
RSP: 0018:ffffc900049af628 EFLAGS: 00010287
RAX: ffffffff8243a678 RBX: ffff8880516bf488 RCX: 0000000000080000
RDX: ffffc9000cd4c000 RSI: 0000000000000c95 RDI: 0000000000000c96
RBP: ffff888079cb8001 R08: ffff8880516bf48f R09: 1ffff1100a2d7e91
R10: dffffc0000000000 R11: ffffed100a2d7e92 R12: ffff888051cf2400
R13: ffff88805778aae0 R14: ffff8880516bf488 R15: 000000000000000a
FS:  00007f32927f66c0(0000) GS:ffff8881260cc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000003000 CR3: 00000000291f0000 CR4: 0000000000350ef0
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:2151
 block_write_begin+0x8a/0x120 fs/buffer.c:2262
 bfs_write_begin+0x35/0xd0 fs/bfs/file.c:179
 generic_perform_write+0x2c7/0x910 mm/filemap.c:4103
 generic_file_write_iter+0x10f/0x540 mm/filemap.c:4246
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x54b/0xa90 fs/read_write.c:684
 ksys_write+0x145/0x250 fs/read_write.c:736
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f329498e969
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:00007f32927f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f3294bb5fa0 RCX: 00007f329498e969
RDX: 000000000000fecc RSI: 00002000000008c0 RDI: 0000000000000004
RBP: 00007f3294a10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3294bb5fa0 R15: 00007ffeb8970878
 </TASK>