From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] NET: fix kernel panic from no dev->hard_header_len
 space
Date: Tue, 01 Aug 2006 17:38:43 -0700 (PDT)
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From: Krzysztof Halasa <khc@pm.waw.pl>
Date: Wed, 02 Aug 2006 02:24:43 +0200

> Do you mean IP calls hard_header() which, in turn, does skb_push()?
> 
> How about Ethernet - is it safe? There is hard_header() which blindly
> adds 14 bytes.

I think Alexey is saying that setting ->hard_header() creates an
agreement between the device and IP that IP will make sure
that dev->hard_header_len bytes are available in the header
area.