[v6.1] WARNING in bfs_get_block

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4931e0e1673d Linux 6.1.170
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1263fb48580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f0605c5af04d7603
dashboard link: https://syzkaller.appspot.com/bug?extid=615f4f94914be8224a24
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4c1b2399e351/disk-4931e0e1.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/feb034d7563a/vmlinux-4931e0e1.xz
kernel image: https://storage.googleapis.com/syzbot-assets/424a14bbc862/bzImage-4931e0e1.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+615f4f...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 14043 at fs/buffer.c:1081 mark_buffer_dirty+0x383/0x7a0 fs/buffer.c:1081
Modules linked in:
CPU: 1 PID: 14043 Comm: syz.3.1891 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:mark_buffer_dirty+0x383/0x7a0 fs/buffer.c:1081
Code: 83 71 e2 ff 49 8b 3f be 04 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d e9 fc a9 fc ff e8 27 65 91 ff e9 43 ff ff ff e8 1d 65 91 ff <0f> 0b e9 ba fc ff ff e8 11 65 91 ff 0f 0b e9 00 fd ff ff e8 05 65
RSP: 0018:ffffc90003fd7808 EFLAGS: 00010283
RAX: ffffffff81f11033 RBX: ffff888073a57cb0 RCX: 0000000000080000
RDX: ffffc9000eab9000 RSI: 00000000000060f7 RDI: 00000000000060f8
RBP: ffff888054bde601 R08: ffff888073a57cb7 R09: 1ffff1100e74af96
R10: dffffc0000000000 R11: ffffed100e74af97 R12: ffff888053a68160
R13: 0000000000000200 R14: ffff8880514e7800 R15: 000000000000000a
FS: 00007f832269b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8fedfea4c0 CR3: 00000000644ee000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bfs_move_block fs/bfs/file.c:43 [inline]
bfs_move_blocks fs/bfs/file.c:56 [inline]
bfs_get_block+0x58f/0xa50 fs/bfs/file.c:125
__block_write_begin_int+0x55d/0x1a80 fs/buffer.c:1991
__block_write_begin fs/buffer.c:2041 [inline]
block_write_begin+0x96/0x1e0 fs/buffer.c:2102
bfs_write_begin+0x31/0xd0 fs/bfs/file.c:177
generic_perform_write+0x2fa/0x5c0 mm/filemap.c:3862
__generic_file_write_iter+0x148/0x2a0 mm/filemap.c:3960
generic_file_write_iter+0xab/0x2e0 mm/filemap.c:3989
call_write_iter include/linux/fs.h:2265 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x4b1/0xa30 fs/read_write.c:584
ksys_write+0x14c/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f832179cdd9
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:00007f832269b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8321a15fa0 RCX: 00007f832179cdd9
RDX: 000000000000fecc RSI: 00002000000008c0 RDI: 0000000000000007
RBP: 00007f8321832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8321a16038 R14: 00007f8321a15fa0 R15: 00007ffd15b0baf8
</TASK>


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