------------[ cut here ]------------
WARNING: CPU: 0 PID: 5321 at fs/buffer.c:1186 mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1186
Modules linked in:
CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted 6.15.0-rc4-syzkaller-00051-g7a13c14ee59d #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:mark_buffer_dirty+0x2a9/0x410 fs/buffer.c:1186
Code: 4c 89 f7 e8 79 0d de ff 49 8b 3e be 20 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 c4 34 fc ff e8 5f 18 7c ff eb 8c e8 58 18 7c ff 90 <0f> 0b 90 e9 95 fd ff ff e8 4a 18 7c ff 90 0f 0b 90 e9 bf fd ff ff
RSP: 0018:ffffc9000d47eb88 EFLAGS: 00010293
RAX: ffffffff8243a7f8 RBX: ffff8880436a4bc8 RCX: ffff88801f5c0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffff888051c04001 R08: ffff8880436a4bcf R09: 1ffff110086d4979
R10: dffffc0000000000 R11: ffffed10086d497a R12: ffff88805350a800
R13: ffff8880436a4740 R14: ffff8880436a4bc8 R15: 000000000000000a
FS:  00007f23102656c0(0000) GS:ffff88808d6cc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2310285700 CR3: 0000000042486000 CR4: 0000000000352ef0
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
 __kernel_write_iter+0x390/0x860 fs/read_write.c:617
 __kernel_write+0xef/0x150 fs/read_write.c:637
 __dump_emit+0x206/0x310 fs/coredump.c:808
 elf_core_dump+0x2ca2/0x3900 fs/binfmt_elf.c:2107
 do_coredump+0x1ec8/0x2a30 fs/coredump.c:759
 get_signal+0x10d9/0x1310 kernel/signal.c:3019
 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:231
 exc_page_fault+0x91/0x110 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 002b:00002000000002c8 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f230f5b6160 RCX: 00007f230f38e969
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000001000000
RBP: 00007f230f410ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f230f5b6160 R15: 00007ffd90e490c8
 </TASK>