------------[ cut here ]------------
!buffer_uptodate(bh)
WARNING: fs/buffer.c:1080 at mark_buffer_dirty+0x299/0x410 fs/buffer.c:1080, CPU#1: syz.4.21/6547
Modules linked in:
CPU: 1 UID: 0 PID: 6547 Comm: syz.4.21 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:mark_buffer_dirty+0x299/0x410 fs/buffer.c:1080
Code: 4c 89 f7 e8 19 58 da ff 49 8b 3e be 40 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 94 5e fb ff e8 ff 17 70 ff eb 8c e8 f8 17 70 ff 90 <0f> 0b 90 e9 a5 fd ff ff e8 ea 17 70 ff 90 0f 0b 90 e9 cf fd ff ff
RSP: 0018:ffffc90003a07488 EFLAGS: 00010293
RAX: ffffffff82557df8 RBX: ffff888055ec0910 RCX: ffff888027825c40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffff88802caae001 R08: ffff888055ec0917 R09: 1ffff1100abd8122
R10: dffffc0000000000 R11: ffffed100abd8123 R12: ffff888070a06000
R13: ffff888055e943a0 R14: ffff888055ec0910 R15: 000000000000000f
FS:  00007f24cf0e16c0(0000) GS:ffff88812534a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f24ce1e8600 CR3: 000000007634a000 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+0x6c6/0x1910 fs/buffer.c:2035
 block_write_begin+0x8d/0x120 fs/buffer.c:2146
 bfs_write_begin+0x35/0xd0 fs/bfs/file.c:180
 generic_perform_write+0x2e2/0x8f0 mm/filemap.c:4324
 generic_file_write_iter+0x14a/0x680 mm/filemap.c:4467
 do_iter_readv_writev+0x619/0x8c0 fs/read_write.c:-1
 vfs_writev+0x33c/0x990 fs/read_write.c:1059
 do_pwritev fs/read_write.c:1155 [inline]
 __do_sys_pwritev2 fs/read_write.c:1213 [inline]
 __se_sys_pwritev2+0x184/0x2a0 fs/read_write.c:1204
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f24ce19aeb9
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:00007f24cf0e1028 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f24ce415fa0 RCX: 00007f24ce19aeb9
RDX: 0000000000000001 RSI: 00002000000001c0 RDI: 0000000000000005
RBP: 00007f24ce208c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000e7b R11: 0000000000000246 R12: 0000000000000000
R13: 00007f24ce416038 R14: 00007f24ce415fa0 R15: 00007fff311277c8
 </TASK>