From: Hannes Frederic Sowa <hannes@stressinduktion.org>
Subject: Re: [PATCH v2 1/4] siphash: add cryptographically secure hashtable
 function
Date: Thu, 15 Dec 2016 13:50:02 +0100
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Cc: Netdev <netdev@vger.kernel.org>,
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To: David Laight <David.Laight@ACULAB.COM>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>
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On 15.12.2016 13:28, David Laight wrote:
> From: Hannes Frederic Sowa
>> Sent: 15 December 2016 12:23
> ...
>> Hmm? Even the Intel ABI expects alignment of unsigned long long to be 8
>> bytes on 32 bit. Do you question that?
> 
> Yes.
> 
> The linux ABI for x86 (32 bit) only requires 32bit alignment for u64 (etc).

Hmm, u64 on 32 bit is unsigned long long and not unsigned long. Thus I
am actually not sure if the ABI would say anything about that (sorry
also for my wrong statement above).

Alignment requirement of unsigned long long on gcc with -m32 actually
seem to be 8.