syzbot has bisected this issue to:
commit ffe945e633b527d5a4577b42cbadec3c7cbcf096
Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Date: Wed Jun 3 23:00:09 2020 +0000
khugepaged: do not stop collapse if less than half PTEs are referenced
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17356c2f100000
start commit: e44f65fd xen-netfront: remove redundant assignment to vari..
git tree: net-next
final oops: https://syzkaller.appspot.com/x/report.txt?x=14b56c2f100000
console output: https://syzkaller.appspot.com/x/log.txt?x=10b56c2f100000
kernel config: https://syzkaller.appspot.com/x/.config?x=829871134ca5e230
dashboard link: https://syzkaller.appspot.com/bug?extid=ed318e8b790ca72c5ad0
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=113406a7100000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=175597d3100000
Reported-by: syzbot+ed318e8b790ca72c5ad0@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: ffe945e633b5 ("khugepaged: do not stop collapse if less than half PTEs are referenced")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
