From mboxrd@z Thu Jan  1 00:00:00 1970
From: mbizon@freebox.fr (Maxime Bizon)
Date: Thu, 11 Oct 2012 13:47:35 +0200
Subject: alignment faults in 3.6
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To: linux-arm-kernel@lists.infradead.org
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On Thu, 2012-10-11 at 13:28 +0200, Eric Dumazet wrote:

> You probably are aware that a driver can use : 
> 
> - a fragment to hold the frame given by the hardware, with whatever
> alignment is needed by the hardware.
> 
> Then allocate an skb with enough room (128 bytes) to pull the headers as
> needed later.
> 
> skb = netdev_alloc_skb_ip_align(dev, 128);

What happen at tx time, supposing that same hardware cannot do SG ?

Aren't we going to memcpy the data into the head ?

-- 
Maxime