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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 580C1C433F5 for ; Fri, 7 Jan 2022 14:16:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc: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=/JUhNuRSv5AT/tiKL7hTS7JsaGoi2TNzL4hnCPulO64=; b=aLghySyUA6Hv0U J0D17c4JLqfhh/wO5AuLCHCDTfrAsxD6TaolUpAfe3sDaFxLKcCrDdlKBBxSD0C7g2/MSdsii55FB LPyl9rLQGeRPDb5LKpCslppzZj/n3/XWeFXLXB85ZFg+9s3qS0Lcrp/VeGveasvlRfSzO/33X3m6f V6ytZl3UzCOpCPb3zAdvsRpjX9h5sP7MN8b7vM72c2oOnXr4HHnq8wwqjecpGTfFTwfOEYRDKjzb5 k7FqYhAvrlOB/UaB40HbCDR3nSVLx4S3xoyf5OUfVvDYggOy/tqdLCNYxdT1K0Qzh65ThE9g+ibiK gwLM47hWDx43mMptHeHw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n5q1b-0048DT-Sc; Fri, 07 Jan 2022 14:15:23 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n5q1Y-0048CC-PH for linux-arm-kernel@lists.infradead.org; Fri, 07 Jan 2022 14:15:22 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6E1A513A1; Fri, 7 Jan 2022 06:15:19 -0800 (PST) Received: from FVFF77S0Q05N (unknown [10.57.7.134]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id AE4523F774; Fri, 7 Jan 2022 06:15:18 -0800 (PST) Date: Fri, 7 Jan 2022 14:15:16 +0000 From: Mark Rutland To: Andre Przywara Cc: linux-arm-kernel@lists.infradead.org, Jaxson Han Subject: Re: [boot-wrapper PATCH v2 7/9] pointer auth: Document CPU feature bit mask Message-ID: References: <20211222181607.1203191-1-andre.przywara@arm.com> <20211222181607.1203191-8-andre.przywara@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20211222181607.1203191-8-andre.przywara@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220107_061520_935538_28E6158C X-CRM114-Status: GOOD ( 15.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 On Wed, Dec 22, 2021 at 06:16:05PM +0000, Andre Przywara wrote: > When checking for the pointer authentication feature, we actually look > for *four* different CPUID feature sets. > Add a comment to make it more obvious that the 0xff is not a typo. > > Signed-off-by: Andre Przywara Thanks; applied. Mark. > --- > arch/aarch64/boot.S | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S > index bfbb6ec..27ba449 100644 > --- a/arch/aarch64/boot.S > +++ b/arch/aarch64/boot.S > @@ -38,7 +38,8 @@ ASM_FUNC(_start) > > /* Enable pointer authentication if present */ > mrs x1, id_aa64isar1_el1 > - ldr x2, =(((0xff) << 24) | (0xff << 4)) > + /* We check for APA+API and GPA+GPI */ > + ldr x2, =((0xff << 24) | (0xff << 4)) > and x1, x1, x2 > cbz x1, 1f > > -- > 2.25.1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel