From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [RFC] New Qlogic 10Gb Ethernet driver for 2.6.28
Date: Fri, 22 Aug 2008 14:43:43 -0700 (PDT)
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From: Ron Mercer <ron.mercer@qlogic.com>
Date: Fri, 22 Aug 2008 10:46:26 -0700

> On Fri, Aug 22, 2008 at 02:42:52AM -0700, David Miller wrote:
> > I also notice that this driver does not do:
> > 
> > 	skb_reserve(skb, NET_IP_ALIGN);
> > 
> > on RX packets to get the IP headers properly 4-byte aligned aligned
> > after the ethernet header.
> 
> The chip currenly has problems with 2-byte aligned receive buffers.
> It will be fixed in the next turn.

If the chip cannot handle this, you will need to copy into a properly
aligned buffer.

Otherwise some RISC platforms will take unaligned access traps, which
run extremely slowly, when 32-bit and larger members of the protocol
headers are read by the networking stack.