syzbot has bisected this bug to:
commit 6dc4f100c175dd0511ae8674786e7c9006cdfbfa
Author: Ming Lei <ming.lei@xxxxxxxxxx>
Date: Fri Feb 15 11:13:19 2019 +0000
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1674423ee00000
start commit: 46cf053e Linux 5.5-rc3
git tree: upstream
final crash: https://syzkaller.appspot.com/x/report.txt?x=1574423ee00000
console output: https://syzkaller.appspot.com/x/log.txt?x=1174423ee00000
kernel config: https://syzkaller.appspot.com/x/.config?x=ed9d672709340e35
dashboard link: https://syzkaller.appspot.com/bug?extid=2b9e54155c8c25d8d165
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=152bdc56e00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=159c489ee00000
Reported-by: syzbot+2b9e54155c8c25d8d165@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate
over multi-page bvec")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection