From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gao feng <gaofeng@cn.fujitsu.com>
Subject: Re: [PATCH] route:ip_rt_frag_needed always return unzero
Date: Wed, 19 Oct 2011 16:07:46 +0800
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Cc: Eric Dumazet <eric.dumazet@gmail.com>, davem@davemloft.net,
	kuznet@ms2.inr.ac.ru, jmorris@namei.org, netdev@vger.kernel.org
To: Steffen Klassert <steffen.klassert@secunet.com>
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2011.10.19 15:26, Steffen Klassert wrote:

> 
> On udp and raw sockets, the user is responsible to adjust the packet
> size according to the mtu value he may find in the socket's error queue.
> So we shoud provide the user with this information, even in the unlikely
> case where we could not create an inet_peer.
> 

Agree.Maybe we should modify mtu immediately when create inet_peer failed

> 
> It is valid in the sense that we should not provide the user
> with a mtu information if we know that the value we got from
> the icmp packet ist bogus. But perhaps we can think about
> making the check for a valid mtu unconditionally and let
> ip_rt_frag_needed return a valid mtu in any case.
> 
> 

I think we should return the pmtu in icmp packet to the raw socket,
and the valid mtu to tcp_v4_err or something else.

thanks Steffen.