Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935948AbcLOMuJ (ORCPT ); Thu, 15 Dec 2016 07:50:09 -0500 Received: from out3-smtp.messagingengine.com ([66.111.4.27]:59480 "EHLO out3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755419AbcLOMuG (ORCPT ); Thu, 15 Dec 2016 07:50:06 -0500 X-ME-Sender: X-Sasl-enc: 57DIYVyMgytZMVVdKKiiLE+4XY3eTebixGeDCXfwLzV1 1481806205 Subject: Re: [PATCH v2 1/4] siphash: add cryptographically secure hashtable function To: David Laight , "Jason A. Donenfeld" References: <20161214035927.30004-1-Jason@zx2c4.com> <8ea3fdff-23c4-b81d-2588-44549bd2d8c1@stressinduktion.org> <063D6719AE5E284EB5DD2968C1650D6DB02401ED@AcuExch.aculab.com> <707472e1-b385-836d-c4c6-791c1dcc0776@stressinduktion.org> <063D6719AE5E284EB5DD2968C1650D6DB02402C0@AcuExch.aculab.com> Cc: Netdev , "kernel-hardening@lists.openwall.com" , Jean-Philippe Aumasson , LKML , Linux Crypto Mailing List , "Daniel J . Bernstein" , Linus Torvalds , Eric Biggers From: Hannes Frederic Sowa Message-ID: <0f3c3694-c00b-aae2-5b08-25bc64bf6372@stressinduktion.org> Date: Thu, 15 Dec 2016 13:50:02 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <063D6719AE5E284EB5DD2968C1650D6DB02402C0@AcuExch.aculab.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 579 Lines: 18 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.