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=-8.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 BD0E1C2D0E4 for ; Tue, 17 Nov 2020 18:22:01 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DF04520888 for ; Tue, 17 Nov 2020 18:22:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="N4Zg6pyv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF04520888 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=xmission.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Subject:MIME-Version:Message-ID:In-Reply-To:Date: References:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=i54YKSEorY6+F3y8vXgGosESIJ5MQ+4gZ8aMOqcmuHc=; b=N4Zg6pyv7x4UpoXgWPSl109+R ksNoQUhvszKFeE53RikCZFTFaYkcWeUsNUO9q5tHI4rR/fwphNtZGlAqR8M2GQs3gwntzyRlRJIhz l1o6Wvojcq4vpqWwiUjE2T5kJP6ltBgKetTYIm+vRhq0bO6SyRl8JP9OOrY4Rw33BV/yIqgw45N2O ghpZLyfCL8yJFeXN9XurcWEAOgJyz9flCaDgu+LV9uqTZDIRd7FuyrO8iHR5N82q2Era96Y2xmNQf Wlw5Iqu2qUiiPjR3CnjKJRWlnquDfAHwA7rqDSBHkqkDZCr6aDxXXvtKLbxz/gR8qEupcnxF1WDq0 7LkJfgySg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kf5bT-0004MA-20; Tue, 17 Nov 2020 18:21:19 +0000 Received: from out02.mta.xmission.com ([166.70.13.232]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kf5XK-0002Ok-Fx for linux-arm-kernel@lists.infradead.org; Tue, 17 Nov 2020 18:17:09 +0000 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1kf5XB-00DV8E-St; Tue, 17 Nov 2020 11:16:54 -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 1kf5XA-004v0U-Rf; Tue, 17 Nov 2020 11:16:53 -0700 From: ebiederm@xmission.com (Eric W. Biederman) To: Peter Collingbourne References: Date: Tue, 17 Nov 2020 12:16:35 -0600 In-Reply-To: (Peter Collingbourne's message of "Mon, 16 Nov 2020 19:17:23 -0800") Message-ID: <87a6vfdf24.fsf@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1kf5XA-004v0U-Rf; ; ; mid=<87a6vfdf24.fsf@x220.int.ebiederm.org>; ; ; hst=in02.mta.xmission.com; ; ; ip=68.227.160.95; ; ; frm=ebiederm@xmission.com; ; ; spf=neutral X-XM-AID: U2FsdGVkX198FaP5HgN4dI/5wsAe2ngeLWpuhYSDD6U= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: [PATCH v17 0/3] arm64: expose FAR_EL1 tag bits in siginfo 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) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201117_131702_642869_B08785ED X-CRM114-Status: GOOD ( 17.32 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Catalin Marinas , Helge Deller , Kevin Brodsky , Oleg Nesterov , linux-api@vger.kernel.org, "James E.J. Bottomley" , Kostya Serebryany , Linux ARM , Andrey Konovalov , David Spickett , Vincenzo Frascino , Will Deacon , Dave Martin , Evgenii Stepanov Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Peter Collingbourne writes: > The kernel currently clears the tag bits (i.e. bits 56-63) in the fault > address exposed via siginfo.si_addr and sigcontext.fault_address. However, > the tag bits may be needed by tools in order to accurately diagnose > memory errors, such as HWASan [1] or future tools based on the Memory > Tagging Extension (MTE). > > We should not stop clearing these bits in the existing fault address > fields, because there may be existing userspace applications that are > expecting the tag bits to be cleared. Instead, introduce a flag in > sigaction.sa_flags, SA_EXPOSE_TAGBITS, and only expose the tag bits > there if the signal handler has this flag set. > > In order to allow userspace to determine whether SA_EXPOSE_TAGBITS > is supported, we first introduce a mechanism for userspace to detect > kernel support for SA_* flags. > > These patches need to be applied on top of: > https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git signal-for-v5.11 The first two patches look good and I have applied them. While I was at it I added Link tags to the LKML postings to the entire series. I don't think anyone has merged my branch into another so it should still be safe. Eric _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel