loop6: detected capacity change from 0 to 64
------------[ cut here ]------------
!buffer_uptodate(bh)
WARNING: fs/buffer.c:991 at mark_buffer_dirty+0x299/0x410 fs/buffer.c:991, CPU#1: syz.6.2346/13970
Modules linked in:
CPU: 1 UID: 0 PID: 13970 Comm: syz.6.2346 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
RIP: 0010:mark_buffer_dirty+0x299/0x410 fs/buffer.c:991
Code: 4c 89 f7 e8 99 00 d8 ff 49 8b 3e be 40 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 74 52 fb ff e8 9f f8 67 ff eb 8c e8 98 f8 67 ff 90 <0f> 0b 90 e9 a5 fd ff ff e8 8a f8 67 ff 90 0f 0b 90 e9 cf fd ff ff
RSP: 0018:ffffc9000de2f828 EFLAGS: 00010287
RAX: ffffffff825fd9c8 RBX: ffff888039038d20 RCX: 0000000000080000
RDX: ffffc9000fb31000 RSI: 0000000000001ea5 RDI: 0000000000001ea6
RBP: 0000000000000201 R08: ffff888039038d27 R09: 1ffff110072071a4
R10: dffffc0000000000 R11: ffffed10072071a5 R12: 000000000000000a
R13: ffff888039038d20 R14: ffff8880535901c0 R15: dffffc0000000000
FS:  00007fbe081f66c0(0000) GS:ffff888124dd1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe09feb840 CR3: 000000007b359000 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+0x5c6/0xb50 fs/bfs/file.c:126
 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2030
 block_write_begin+0x8d/0x120 fs/buffer.c:2144
 bfs_write_begin+0x35/0xd0 fs/bfs/file.c:180
 generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4374
 generic_file_write_iter+0xae/0x330 mm/filemap.c:4517
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x612/0xba0 fs/read_write.c:687
 ksys_write+0x150/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbe09f9e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbe081f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fbe0a225fa0 RCX: 00007fbe09f9e159
RDX: 000000000000fecc RSI: 00002000000008c0 RDI: 0000000000000004
RBP: 00007fbe0a03506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbe0a226038 R14: 00007fbe0a225fa0 R15: 00007fffbc3a3ea8
 </TASK>