From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Peter Huang (Peng)" <peter.huangpeng@huawei.com>
Subject: =?utf-8?Q?=E7=AD=94=E5=A4=8D:_=E7=AD=94=E5=A4=8D:_=5BPATCH=5D_set_fake=5Fr?=
	=?utf-8?Q?table's_dst_to_NULL_to_avoid_ker?=	=?utf-8?Q?nel_Oops.?=
Date: Thu, 29 Mar 2012 17:38:59 +0800
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Cc: linux-kernel@vger.kernel.org, harry.majun@huawei.com,
	zhoukang7@huawei.com, 'netdev' <netdev@vger.kernel.org>
To: 'Eric Dumazet' <eric.dumazet@gmail.com>
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Thks for your mail.

>Check net/bridge/br_netfilter.c and commits e688a6048076 (net: introduce
>DST_NOPEER dst flag )  4adf0af6818f3ea5 (bridge: send correct MTU value
>in PMTU (revised))

This patch already included in kernel-3.3, but for our case, virtual tap device's delayed
Deletion will also cause kernel oops even in kernel3.3.

>Apparently bug is because struct net_bridge is freed while its embedded
>fake_rtable is still used by some packets.

>I am not sure we are allowed to NULLify skb->dst, it might break
>netfilter.

Are you familiar with fake_rtable? I search the source, but only find one op that operate on the MTU.

>Maybe real fix would be to use a non embedded dst.

I agreed with you to, so at least until now this problem still exsits in the latest kernel, I will also look into it,
And try to modify it from the root.

Thanks again.