From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michal Schmidt <mschmidt@redhat.com>
Subject: Re: [PATCH] ipv6: sit: update mtu check to take care of gso packets
Date: Tue, 17 Dec 2013 15:22:37 +0100
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To: Eric Dumazet <eric.dumazet@gmail.com>,
	David Miller <davem@davemloft.net>
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On 12/16/2013 03:31 PM, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
> 
> While testing my changes for TSO support in SIT devices,
> I was using sit0 tunnel which appears to include nopmtudisc flag.
> 
> But using :
> 
> ip tun add sittun mode sit remote $REMOTE_IPV4 local $LOCAL_IPV4 \
>    dev $IFACE
> 
> We get a tunnel which rejects too long packets because of the mtu check
> which is not yet GSO aware.
> 
> erd:~# ip tunnel
> sittun: ipv6/ip  remote 10.246.17.84  local 10.246.17.83  ttl inherit  6rd-prefix 2002::/16 
> sit0: ipv6/ip  remote any  local any  ttl 64  nopmtudisc 6rd-prefix 2002::/16 
> 
> This patch is based on an excellent report from
> Michal Shmidt.
> 
> In the future, we probably want to extend the MTU check to do the
> right thing for GSO packets...
> 
> Fixes: ("61c1db7fae21 ipv6: sit: add GSO/TSO support")
> Reported-by: Michal Schmidt <mschmidt@redhat.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Tested-by: Michal Schmidt <mschmidt@redhat.com>

It works fine now. Thanks.
Michal