From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] vlan: Fix the ingress VLAN_FLAG_REORDER_HDR check v2
Date: Sun, 05 Jun 2011 14:14:46 -0700 (PDT)
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From: Changli Gao <xiaosuo@gmail.com>
Date: Fri, 3 Jun 2011 11:59:26 +0800

> On Fri, Jun 3, 2011 at 11:34 AM, padmanabh ratnakar
> <pratnakarlx@gmail.com> wrote:
>> Doesnt __vlan_put_tag()/vlan_insert_tag() depend on skb->data pointing
>> to ethernet header.
>> Is'nt the skb->data pointing past ethernet header in netif_receive_skb().
>> Am I missing anything?
> 
> Yes, you are right. skb->data should be adjusted before feeding to
> vlan_insert_tag(), or we make vlan_insert_tag() rely on
> skb->mac_header instead.

I told you guys this is not simple stuff :-)

Even here we have 3 or 4 people who study this code all the time, and
are still having trouble sorting out all of these details.