From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH] Consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECK Date: Wed, 27 Feb 2013 15:21:06 -0800 Message-ID: <512E94E2.50809@zytor.com> 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> <512E9480.7020306@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <512E9480.7020306@codeaurora.org> List-Archive: List-Post: To: Stephen Boyd 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 List-ID: On 02/27/2013 03:19 PM, Stephen Boyd wrote: > 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/ > I can, although I would prefer if it came with the uaccess/usercopy unification. -hpa