------------[ cut here ]------------
!buffer_uptodate(bh)
WARNING: fs/buffer.c:991 at mark_buffer_dirty+0x299/0x410 fs/buffer.c:991, CPU#0: syz.0.0/5327
Modules linked in:
CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:mark_buffer_dirty+0x299/0x410 fs/buffer.c:991
Code: 4c 89 f7 e8 79 89 d8 ff 49 8b 3e be 40 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 74 52 fb ff e8 7f 37 69 ff eb 8c e8 78 37 69 ff 90 <0f> 0b 90 e9 a5 fd ff ff e8 6a 37 69 ff 90 0f 0b 90 e9 cf fd ff ff
RSP: 0018:ffffc9000de8f270 EFLAGS: 00010283
RAX: ffffffff825def18 RBX: ffff88804386d9a0 RCX: 0000000000100000
RDX: ffffc9000f4b1000 RSI: 0000000000054649 RDI: 000000000005464a
RBP: ffffc9000de8f401 R08: ffff88804386d9a7 R09: 1ffff1100870db34
R10: dffffc0000000000 R11: ffffed100870db35 R12: ffff8880129f6000
R13: dffffc0000000000 R14: 00000000000000e6 R15: 0000000000000026
FS:  00007f8be61816c0(0000) GS:ffff88808c533000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000136cb000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 udf_bitmap_new_block fs/udf/balloc.c:348 [inline]
 udf_new_block+0x17d9/0x1c00 fs/udf/balloc.c:722
 inode_getblk fs/udf/inode.c:898 [inline]
 udf_map_block+0x138e/0x4270 fs/udf/inode.c:451
 __udf_get_block+0x52/0x250 fs/udf/inode.c:465
 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2027
 block_write_begin+0x8d/0x120 fs/buffer.c:2138
 udf_write_begin+0x118/0x270 fs/udf/inode.c:259
 generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4364
 udf_file_write_iter+0x2e8/0x6c0 fs/udf/file.c:112
 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: 0033:0x7f8be539e0d9
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:00007f8be6180fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8be5626090 RCX: 00007f8be539e0d9
RDX: 000000000000ffc9 RSI: 0000200000000140 RDI: 000000000000000d
RBP: 00007f8be5435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8be5626128 R14: 00007f8be5626090 R15: 00007ffef6d34418
 </TASK>