From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758882Ab3B0XTb (ORCPT ); Wed, 27 Feb 2013 18:19:31 -0500 Received: from wolverine01.qualcomm.com ([199.106.114.254]:7189 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758468Ab3B0XT3 (ORCPT ); Wed, 27 Feb 2013 18:19:29 -0500 X-IronPort-AV: E=Sophos;i="4.84,751,1355126400"; d="scan'208";a="26883958" Message-ID: <512E9480.7020306@codeaurora.org> Date: Wed, 27 Feb 2013 15:19:28 -0800 From: Stephen Boyd User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:17.0) Gecko/20130215 Thunderbird/17.0.3 MIME-Version: 1.0 To: "H. Peter Anvin" CC: Arnd Bergmann , Andrew Morton , linux-kernel@vger.kernel.org, Ingo Molnar , linux-parisc@vger.kernel.org, linux-s390@vger.kernel.org, Arjan van de Ven , Helge Deller , Heiko Carstens , Stephen Rothwell , Chris Metcalf Subject: Re: [PATCH] Consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECK References: <1361934016-22630-1-git-send-email-sboyd@codeaurora.org> <201302272032.21014.arnd@arndb.de> <512E6FA9.4060504@codeaurora.org> <512E8664.3070903@zytor.com> <512E8E48.8020007@codeaurora.org> <512E8ECF.1080307@zytor.com> In-Reply-To: <512E8ECF.1080307@zytor.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 On 02/27/13 14:55, H. Peter Anvin wrote: > On 02/27/2013 02:52 PM, Stephen Boyd wrote: >> On 02/27/13 14:19, H. Peter Anvin wrote: >>> On 02/27/2013 12:42 PM, Stephen Boyd wrote: >>>>> It's fine to do your patch as a first step though, which would not >>>>> change the behavior. >>>> A lot of arches seem to not want to enable it because false positives >>>> are everywhere. It really depends on how good the compiler is at doing >>>> constant propagation and dead code removal. >>>> >>> Although some of the cases I have seen being flagged as "false >>> positives" have been real bugs. >> There were so many false-positives on x86_64 that Andrew eventually >> dropped my patch to add support for this option to the copy_from_user() >> function there. >> > I would probably have taken it, especially if it came with more x86-64 > to i386 unification. > > It's an option, though. You acked the patch[1]. Will you pick it up? [1] https://patchwork.kernel.org/patch/833192/ -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation