From mboxrd@z Thu Jan  1 00:00:00 1970
From: Maxime Bizon <mbizon@freebox.fr>
Subject: Re: kernel 3.2.27 on arm: WARNING: at mm/page_alloc.c:2109
 __alloc_pages_nodemask+0x1d4/0x68c()
Date: Fri, 05 Oct 2012 16:50:59 +0200
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Cc: David Madore <david+ml@madore.org>,
	Francois Romieu <romieu@fr.zoreil.com>, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org, Hugh Dickins <hughd@google.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, 2012-10-05 at 15:02 +0200, Eric Dumazet wrote:

> On Fri, 2012-10-05 at 14:51 +0200, Maxime Bizon wrote:
> 
> > > New convention would be : pass number of needed bytes after current
> > > tail, not after current end.
> > 
> > Fully agree on this
> > 
> 
> Here is the proposal :

Looks fine

What is your plan for the actual pskb_expand_head() code now that you
will have absolute values for headroom & tailroom ?

Because there will still be callers that have no clue of required
tailroom (nor further headroom requirement), like skb_cow() in
vlan_reorder_header().

-- 
Maxime