Re: possible deadlock in dev_mc_unsync

[syzbot]

syzbot suspects this issue was fixed by commit:

commit be74294ffa24f5fbc0d6643842e3e095447e17a2
Author: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Date:   Fri Jun 26 18:24:22 2020 +0000

    net: get rid of lockdep_set_class_and_subclass()

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=110b0fc2900000
start commit:   4a21185c Merge git://git.kernel.org/pub/scm/linux/kernel/g..
git tree:       net
kernel config:  https://syzkaller.appspot.com/x/.config?x=bf3aec367b9ab569
dashboard link: https://syzkaller.appspot.com/bug?extid=08e3d39f3eb8643216be
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11d2b1c5100000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17aed775100000

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

#syz fix: net: get rid of lockdep_set_class_and_subclass()

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