From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rick Jones <rick.jones2@hp.com>
Subject: Re: [RFC] IP_MAX_MTU value
Date: Fri, 21 Dec 2012 10:50:26 -0800
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Cc: David Miller <davem@davemloft.net>, netdev <netdev@vger.kernel.org>
To: Eric Dumazet <erdnetdev@gmail.com>
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On 12/21/2012 10:34 AM, Eric Dumazet wrote:
> On Fri, 2012-12-21 at 10:19 -0800, Rick Jones wrote:
>
>> If you go beyond the protocol limit of an IPv4 datagram, won't it be
>> necessary to  start being a bit more conditional on IPv4 vs IPv6?
>>
>
> This IP_MAX_MTU is really an IPv4 thing (static to net/ipv4/route.c)

OK. Doesn't this:

         if (mtu > IP_MAX_MTU)
                 mtu = IP_MAX_MTU;

mean it should be OK to go to 0xFFFF but not 0x10000?  Since 65535 is 
the limit of an IPv4 datagram and so I would think would be the maximum 
MTU for an IPv4 interface.

rick