------------[ cut here ]------------
WARNING: CPU: 0 PID: 6693 at fs/buffer.c:1183 mark_buffer_dirty+0x2a9/0x410
Modules linked in:
CPU: 0 UID: 0 PID: 6693 Comm: syz.3.94 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:mark_buffer_dirty+0x2a9/0x410
Code: 4c 89 f7 e8 d9 4b dd ff 49 8b 3e be 20 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 d4 02 fc ff e8 9f dd 79 ff eb 8c e8 98 dd 79 ff 90 <0f> 0b 90 e9 95 fd ff ff e8 8a dd 79 ff 90 0f 0b 90 e9 bf fd ff ff
RSP: 0018:ffffc9000290f608 EFLAGS: 00010283
RAX: ffffffff8245cdf8 RBX: ffff88803d54dcb0 RCX: 0000000000080000
RDX: ffffc90003141000 RSI: 0000000000000672 RDI: 0000000000000673
RBP: ffff88801b7c0001 R08: ffff88803d54dcb7 R09: 1ffff11007aa9b96
R10: dffffc0000000000 R11: ffffed1007aa9b97 R12: ffff88802cb4e600
R13: ffff88811a8993a0 R14: ffff88803d54dcb0 R15: 000000000000000a
FS:  00007faeb53426c0(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e9e1ff8 CR3: 0000000117bc2000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 bfs_get_block+0x5da/0xae0
 __block_write_begin_int+0x6b5/0x1900
 block_write_begin+0x8a/0x120
 bfs_write_begin+0x35/0xd0
 generic_perform_write+0x2c5/0x900
 generic_file_write_iter+0x117/0x550
 vfs_write+0x5c9/0xb30
 __x64_sys_pwrite64+0x193/0x220
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faeb458ebe9
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:00007faeb5342038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007faeb47b5fa0 RCX: 00007faeb458ebe9
RDX: 000000000000fdef RSI: 0000200000000140 RDI: 000000000000000c
RBP: 00007faeb4611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000e7c R11: 0000000000000246 R12: 0000000000000000
R13: 00007faeb47b6038 R14: 00007faeb47b5fa0 R15: 00007ffd3139fa48
 </TASK>
