From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 01169C56202 for ; Mon, 23 Nov 2020 15:54:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6002206B6 for ; Mon, 23 Nov 2020 15:54:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732532AbgKWPyI (ORCPT ); Mon, 23 Nov 2020 10:54:08 -0500 Received: from out03.mta.xmission.com ([166.70.13.233]:46892 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730775AbgKWPyI (ORCPT ); Mon, 23 Nov 2020 10:54:08 -0500 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1khE9p-00AOeW-Gq; Mon, 23 Nov 2020 08:53:37 -0700 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1khE9o-002VLF-Gs; Mon, 23 Nov 2020 08:53:37 -0700 From: ebiederm@xmission.com (Eric W. Biederman) To: Catalin Marinas Cc: Peter Collingbourne , Evgenii Stepanov , Kostya Serebryany , Vincenzo Frascino , Dave Martin , Will Deacon , Oleg Nesterov , "James E.J. Bottomley" , Linux ARM , Kevin Brodsky , Andrey Konovalov , linux-api@vger.kernel.org, Helge Deller , David Spickett References: <13cf24d00ebdd8e1f55caf1821c7c29d54100191.1605904350.git.pcc@google.com> <87h7pj1ulp.fsf@x220.int.ebiederm.org> <20201123114935.GD17833@gaia> Date: Mon, 23 Nov 2020 09:53:13 -0600 In-Reply-To: <20201123114935.GD17833@gaia> (Catalin Marinas's message of "Mon, 23 Nov 2020 11:49:36 +0000") Message-ID: <87y2isysra.fsf@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1khE9o-002VLF-Gs;;;mid=<87y2isysra.fsf@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1/ry+q88UTCyU/G2s1YZX7m3LL9GyWOTKk= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: [PATCH v21 1/2] signal: define the SA_EXPOSE_TAGBITS bit in sa_flags X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org Catalin Marinas writes: > On Fri, Nov 20, 2020 at 05:22:58PM -0600, Eric W. Biederman wrote: >> Peter Collingbourne writes: >> >> > Architectures that support address tagging, such as arm64, may want to >> > expose fault address tag bits to the signal handler to help diagnose >> > memory errors. However, these bits have not been previously set, >> > and their presence may confuse unaware user applications. Therefore, >> > introduce a SA_EXPOSE_TAGBITS flag bit in sa_flags that a signal >> > handler may use to explicitly request that the bits are set. >> > >> > The generic signal handler APIs expect to receive tagged addresses. >> > Architectures may specify how to untag addresses in the case where >> > SA_EXPOSE_TAGBITS is clear by defining the arch_untagged_si_addr >> > function. >> > >> > Signed-off-by: Peter Collingbourne >> > Acked-by: "Eric W. Biederman" >> > Link: https://linux-review.googlesource.com/id/I16dd0ed2081f091fce97be0190cb8caa874c26cb >> > --- >> > To be applied on top of: >> > https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git signal-for-v5.11 >> >> I have merged this first patch into signal-for-v5.11 and pushed >> everything out to linux-next. > > Thank you Eric. Assuming this branch won't be rebased, I'll apply the > arm64 changes on top (well, if you rebase it, just let me know so that > we don't end up with duplicate commits in mainline). No. I won't be rebasing it. Not unless something serious problem shows up, and at that point I will be more likely to apply a corrective change on top that you can also grab. Eric