loop2: detected capacity change from 0 to 64
------------[ cut here ]------------
WARNING: CPU: 1 PID: 6853 at fs/buffer.c:1173 mark_buffer_dirty+0x2c6/0x440 fs/buffer.c:1173
Modules linked in:
CPU: 1 UID: 0 PID: 6853 Comm: syz.2.291 Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:mark_buffer_dirty+0x2c6/0x440 fs/buffer.c:1173
Code: 4c 89 f7 e8 fc fd da ff 49 8b 3e be 20 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 27 bc fb ff e8 02 c7 70 ff eb 8b e8 fb c6 70 ff 90 <0f> 0b 90 e9 82 fd ff ff e8 ed c6 70 ff 90 0f 0b 90 e9 a9 fd ff ff
RSP: 0018:ffffc9001b0675e0 EFLAGS: 00010287
RAX: ffffffff8252b345 RBX: ffff88805d5da401 RCX: 0000000000080000
RDX: ffffc9000c3dc000 RSI: 0000000000001c05 RDI: 0000000000001c06
RBP: 0000000000000000 R08: ffffffff8252b0c3 R09: 1ffff1100f4de01d
R10: dffffc0000000000 R11: ffffed100f4de01e R12: 0000000000000200
R13: dffffc0000000000 R14: ffff88807a6f00e8 R15: ffff88805d5da488
FS:  00007fc5208186c0(0000) GS:ffff888125080000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f89af030fe4 CR3: 000000006b94e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bfs_move_block fs/bfs/file.c:44 [inline]
 bfs_move_blocks fs/bfs/file.c:57 [inline]
 bfs_get_block+0x63b/0xb60 fs/bfs/file.c:126
 __block_write_begin_int+0x691/0x1930 fs/buffer.c:2116
 block_write_begin+0x8f/0x120 fs/buffer.c:2227
 bfs_write_begin+0x35/0xd0 fs/bfs/file.c:179
 generic_perform_write+0x329/0xa10 mm/filemap.c:4103
 generic_file_write_iter+0x10e/0x5e0 mm/filemap.c:4246
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x70f/0xd10 fs/read_write.c:684
 ksys_write+0x19d/0x2d0 fs/read_write.c:736
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc51f98e169
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:00007fc520818038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fc51fbb5fa0 RCX: 00007fc51f98e169
RDX: 000000000000fecc RSI: 00002000000008c0 RDI: 0000000000000004
RBP: 00007fc51fa10a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc51fbb5fa0 R15: 00007ffd9c7ada68
 </TASK>