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Date:   Wed, 22 Aug 2018 07:11:41 +0300 (EEST)
From:   Julian Anastasov <ja@ssi.bg>
To:     Cong Wang <xiyou.wangcong@gmail.com>
cc:     syzbot+30209ea299c09d8785c9@syzkaller.appspotmail.com,
        ddstreet@ieee.org, Dmitry Vyukov <dvyukov@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        syzkaller-bugs@googlegroups.com
Subject: Re: unregister_netdevice: waiting for DEV to become free (2)
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	Hello,

On Mon, 20 Aug 2018, Cong Wang wrote:

> For the one I look into, dst_cache doesn't matter, because the xmit
> path doesn't even use tunnel dst_cache at all, and it is ip6tnl0 FB
> device, unlike this one which is tun device.

	Ops, of course, it is dev tun and not ip tun...

> For the one I look into, it seems some fib6_info is not released for
> some reason. It seems to be the one created by addrconf_prefix_route(),
> which is supposed to be released by fib6_clean_tree() I think, but it
> never happens.

	May be, it is not direct reference to dev but one
that is moved to loopback, like from dst, route... The repro.c
creates permanent neighbours and addresses.

Regards

--
Julian Anastasov <ja@ssi.bg>