From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [RFC] net/hsr: Add support for IEC 62439-3 High-availability
 Seamless Redundancy
Date: Thu, 05 Apr 2012 18:31:43 -0400 (EDT)
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From: Ben Hutchings <bhutchings@solarflare.com>
Date: Thu, 5 Apr 2012 20:21:08 +0100

> On Wed, 2012-04-04 at 20:17 -0400, David Miller wrote:
>> From: Arvid Brodin <arvid.brodin@enea.com>
>> Date: Thu, 5 Apr 2012 01:09:48 +0200
>> 
>> > -		icmp_param.data.icmph	   = *icmp_hdr(skb);
>> > +		memcpy(&icmp_param.data.icmph, icmp_hdr(skb),
>> > +						sizeof(icmp_param.data.icmph));
>> 
>> GCC can and will optimize this into an inline assignment, and thus
>> have the same unaligned access problems, because it determines
>> alignment based upon the types involved.
> 
> So presumably icmp_hdr() should be changed to skb_transport_header().

I would not say so.  Otherwise we introduce ugly casts everywhere.