syzbot suspects this bug was fixed by commit:

commit 810507fe6fd5ff3de429121adff49523fabb643a Author: Waiman Long longman@redhat.com Date: Thu Feb 6 15:24:08 2020 +0000

locking/lockdep: Reuse freed chain_hlocks entries

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1008138be00000 start commit: 72825454 Merge branch 'x86-urgent-for-linus' of git://git... git tree: upstream kernel config: https://syzkaller.appspot.com/x/.config?x=9a31528e58cc12e2 dashboard link: https://syzkaller.appspot.com/bug?extid=38f5d5cf7ae88c46b11a syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12a6c439a00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1353c323a00000

If the result looks correct, please mark the bug fixed by replying with:

#syz fix: locking/lockdep: Reuse freed chain_hlocks entries

For information about bisection process see: https://goo.gl/tpsmEJ#bisection