loop7: detected capacity change from 0 to 64
------------[ cut here ]------------
WARNING: CPU: 1 PID: 9129 at fs/buffer.c:1189 mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1189
Modules linked in:
CPU: 1 UID: 0 PID: 9129 Comm: syz.7.845 Not tainted 6.15.0-rc7-next-20250523-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1189
Code: 4c 89 f7 e8 49 ca dd ff 49 8b 3e be 20 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 24 33 fc ff e8 8f 60 7a ff eb 8c e8 88 60 7a ff 90 <0f> 0b 90 e9 95 fd ff ff e8 7a 60 7a ff 90 0f 0b 90 e9 bf fd ff ff
RSP: 0018:ffffc90004d2f608 EFLAGS: 00010283
RAX: ffffffff8245e2a8 RBX: ffff888022cdc9f8 RCX: 0000000000080000
RDX: ffffc9001122f000 RSI: 0000000000001819 RDI: 000000000000181a
RBP: ffff888058db6001 R08: ffff888022cdc9ff R09: 1ffff1100459b93f
R10: dffffc0000000000 R11: ffffed100459b940 R12: ffff88804974b000
R13: ffff88803207e000 R14: ffff888022cdc9f8 R15: 000000000000000f
FS:  00007f2bf4a266c0(0000) GS:ffff888125d56000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002000 CR3: 000000007e340000 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+0x5da/0xae0 fs/bfs/file.c:126
 __block_write_begin_int+0x6b2/0x1900 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+0x2c4/0x910 mm/filemap.c:4103
 generic_file_write_iter+0x10f/0x540 mm/filemap.c:4246
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x548/0xa90 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 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: 0033:0x7f2bf3b8e969
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:00007f2bf4a26038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f2bf3db5fa0 RCX: 00007f2bf3b8e969
RDX: 000000000000fecc RSI: 00002000000008c0 RDI: 0000000000000004
RBP: 00007f2bf3c10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2bf3db5fa0 R15: 00007ffc008814e8
 </TASK>