Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753878AbXFOL4v (ORCPT ); Fri, 15 Jun 2007 07:56:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752449AbXFOL4n (ORCPT ); Fri, 15 Jun 2007 07:56:43 -0400 Received: from mx2.suse.de ([195.135.220.15]:42087 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752407AbXFOL4m (ORCPT ); Fri, 15 Jun 2007 07:56:42 -0400 From: Andi Kleen Organization: SUSE Linux Products GmbH, Nuernberg, GF: Markus Rex, HRB 16746 (AG Nuernberg) To: Arnd Bergmann Subject: Re: [PATCH] Introduce compat_u64 and compat_s64 types Date: Fri, 15 Jun 2007 13:55:57 +0200 User-Agent: KMail/1.9.6 Cc: Benjamin Herrenschmidt , David Woodhouse , Linux Kernel Mailing List , Dave Airlie , linux-arch@vger.kernel.org, Andrew Morton References: <200706150159.l5F1xNgM000459@hera.kernel.org> <200706151128.39566.arnd@arndb.de> <200706151131.38429.arnd@arndb.de> In-Reply-To: <200706151131.38429.arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200706151355.57464.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 870 Lines: 21 On Friday 15 June 2007 11:31:37 Arnd Bergmann wrote: > One common problem with 32 bit system call and ioctl emulation > is the different alignment rules between i386 and 64 bit machines. > A number of drivers work around this by marking the compat > structures as 'attribute((packed))', which is not the right > solution because it breaks all the non-x86 architectures that > want to use the same compat code. Why does it break them? It should just make them a little slower. The network code requires unaligned accesses to work anyways so if your architecture doesn't support them it is already remotely crashable. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/