Re: inconsistent lock state in rxrpc_put_client_conn

syzbot has bisected this bug to:

commit 5273a191dca65a675dc0bcf3909e59c6933e2831
Author: David Howells [off-list ref]
Date:   Thu Jan 30 21:50:36 2020 +0000

    rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1182314ee00000
start commit:   3d80c653 Merge tag 'rxrpc-fixes-20200203' of git://git.ker..
git tree:       net
final crash:    https://syzkaller.appspot.com/x/report.txt?x=1382314ee00000
console output: https://syzkaller.appspot.com/x/log.txt?x=1582314ee00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=95b275782b150c86
dashboard link: https://syzkaller.appspot.com/bug?extid=3f1fd6b8cbf8702d134e
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14ac314ee00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13ec4c5ee00000

Reported-by: syzbot+3f1fd6b8cbf8702d134e@syzkaller.appspotmail.com
Fixes: 5273a191dca6 ("rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect")

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