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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 E1725C43387 for ; Fri, 4 Jan 2019 18:02:31 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 B657D218D3 for ; Fri, 4 Jan 2019 18:02:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="tu7YtcPq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B657D218D3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-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=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=R3IYxo9Qk0czCFyoGD0zKvuqRH8zc6qEP9h0AZxDaMo=; b=tu7YtcPq1bpx/I kIWWYTkSp20rYWmex98wF1ea1q9EpqktRUars7Kyd57HLkn7U14zyvfVwy8xVuebPeKkSw6/sG9FJ PtKc6qVESHWQS/gnZtowXpOxYVjFqdTMiwBkgSmAhyEnL/AyzOJHS015MrBR3ng3eLMxZYxLuQv8l ddljXVh/Ydoq1+ZN5QNoDpY0HmqcPKsK9oV/f1AJOkEJDv+HY4BVfrBkiIDuQIlj65Lm+K+CuR/Bn QfXvXjW1i1NZBDTj/eCQPJjrPLVtJorIun9gF5T5bMqaIlX4BAvbqxOGBneEV8A2aH99swRC2Vi06 u1mIuNbp0XjmMlGfbWlA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gfTng-0007G0-09; Fri, 04 Jan 2019 18:02:28 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gfTnc-0006vo-40 for linux-arm-kernel@lists.infradead.org; Fri, 04 Jan 2019 18:02:25 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D4CCDEBD; Fri, 4 Jan 2019 10:02:21 -0800 (PST) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 955E83F5D4; Fri, 4 Jan 2019 10:02:18 -0800 (PST) Date: Fri, 4 Jan 2019 18:02:16 +0000 From: Mark Rutland To: Pavel Machek Subject: Re: [PATCH v6 07/13] arm64: add basic pointer authentication support Message-ID: <20190104180215.GB7157@lakrids.cambridge.arm.com> References: <20181207183931.4285-1-kristina.martsenko@arm.com> <20181207183931.4285-8-kristina.martsenko@arm.com> <20190103202901.GA21564@amd> <681a2835-1a70-f3c3-3534-7b4cf6139cac@arm.com> <20190104093340.GA28150@amd> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190104093340.GA28150@amd> User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190104_100224_227095_D50D947B X-CRM114-Status: GOOD ( 18.34 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andrew Jones , linux-kernel@vger.kernel.org, Jacob Bramley , Ard Biesheuvel , Marc Zyngier , Catalin Marinas , Adam Wallis , Suzuki K Poulose , Richard Henderson , Christoffer Dall , Kristina Martsenko , kvmarm@lists.cs.columbia.edu, Cyrill Gorcunov , Will Deacon , Ramana Radhakrishnan , Amit Kachhap , Dave P Martin , linux-arm-kernel@lists.infradead.org, Kees Cook Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Jan 04, 2019 at 10:33:40AM +0100, Pavel Machek wrote: > On Fri 2019-01-04 09:21:30, Marc Zyngier wrote: > > On 03/01/2019 20:29, Pavel Machek wrote: > > > On Fri 2018-12-07 18:39:25, Kristina Martsenko wrote: > > >> From: Mark Rutland > > >> > > >> This patch adds basic support for pointer authentication, > > >> allowing userspace to make use of APIAKey, APIBKey, APDAKey, > > >> APDBKey, and APGAKey. The kernel maintains key values for each > > >> process (shared by all threads within), which are initialised to > > >> random values at exec() > > > time. > > > > > > ... > > > > > >> +/* + * We give each process its own keys, which are shared by > > >> all threads. The keys + * are inherited upon fork(), and > > >> reinitialised upon exec*(). + */ +struct ptrauth_keys { + struct > > >> ptrauth_key apia; + struct ptrauth_key apib; + struct ptrauth_key > > >> apda; + struct ptrauth_key apdb; + struct ptrauth_key apga; +}; > > > > > > intstruction_a, data_a, generic_a? Should be easier to understand > > > than "apdb" ... > > > > ... until you realize that these names do match the documentation, > > which makes it even easier to understand how the code uses the > > architecture. > > See how not even the commit log matches the documentation then? The commit message exactly matches the documentation, as it refers to: APIAKey, APIBKey, APDAKey, APDBKey, and APGAKey ... which are the architected names for those registers, in all the documentation. Searching "apga" in the ARM ARM finds all of the relevant information on APGAKey_EL1. Searching "generic_a" finds precisely nothing, as it's a term which you invented, that no-one else has previously used. Likewise for the other key names. > Naming something "apdb" is just bad... Just because the documentation > is evil does not mean it should be followed... It is in no way evil to use the documented names for things. It is unhelpful to make up terminology that no-one else uses. Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel