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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 3C75DC4332B for ; Mon, 11 Jan 2021 17:57:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 15CC4223C8 for ; Mon, 11 Jan 2021 17:57:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389951AbhAKR5i (ORCPT ); Mon, 11 Jan 2021 12:57:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389680AbhAKR5h (ORCPT ); Mon, 11 Jan 2021 12:57:37 -0500 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38C25C0617A4; Mon, 11 Jan 2021 09:56:52 -0800 (PST) Received: from zn.tnic (p200300ec2f088f00ad31e6206ee73146.dip0.t-ipconnect.de [IPv6:2003:ec:2f08:8f00:ad31:e620:6ee7:3146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id D700E1EC04DD; Mon, 11 Jan 2021 18:56:47 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1610387808; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=/5CtVo/UwrBSJWcpm5LHTVgzx79jnr7sh5lj/gNN1EE=; b=r1dRCcuAAzNinHRwv70Jc/k2NLJRF6q7sDui9/+Zn1f8PG48sZQFwQ07YaMmLil58/Jk3e 8Ix8pm+/1koZXCLgJ5Pd/KygG1l+XQOydfsHuyx1X7+DolK4jzI04VBxJp9VDGVeqQI3xa 0TVfTxuAUigDYWZxsnFfYFG320gE/So= Date: Mon, 11 Jan 2021 18:56:43 +0100 From: Borislav Petkov To: Yu-cheng Yu Cc: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang , Pengfei Xu Subject: Re: [PATCH v17 04/26] x86/cpufeatures: Introduce X86_FEATURE_CET and setup functions Message-ID: <20210111175643.GD25645@zn.tnic> References: <20201229213053.16395-1-yu-cheng.yu@intel.com> <20201229213053.16395-5-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20201229213053.16395-5-yu-cheng.yu@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 29, 2020 at 01:30:31PM -0800, Yu-cheng Yu wrote: > @@ -895,6 +903,12 @@ static void init_speculation_control(struct cpuinfo_x86 *c) > } > } > > +static void init_cet_features(struct cpuinfo_x86 *c) > +{ > + if (cpu_has(c, X86_FEATURE_SHSTK) || cpu_has(c, X86_FEATURE_IBT)) > + set_cpu_cap(c, X86_FEATURE_CET); > +} No need for that function - just add this two-liner to bsp_init_intel() and not in get_cpu_cap(). > +static void adjust_combined_cpu_features(void) > +{ > +#ifdef CONFIG_X86_CET_USER > + if (test_bit(X86_FEATURE_SHSTK, (unsigned long *)cpu_caps_cleared) && > + test_bit(X86_FEATURE_IBT, (unsigned long *)cpu_caps_cleared)) > + setup_clear_cpu_cap(X86_FEATURE_CET); > +#endif There's no need for this function... > +} > + > /* > * We parse cpu parameters early because fpu__init_system() is executed > * before parse_early_param(). > @@ -1252,9 +1276,19 @@ static void __init cpu_parse_early_param(void) > if (cmdline_find_option_bool(boot_command_line, "noxsaves")) > setup_clear_cpu_cap(X86_FEATURE_XSAVES); > > + /* > + * CET states are XSAVES states and options must be parsed early. > + */ > +#ifdef CONFIG_X86_CET_USER > + if (cmdline_find_option_bool(boot_command_line, "no_user_shstk")) > + setup_clear_cpu_cap(X86_FEATURE_SHSTK); ... when you can do setup_clear_cpu_cap(X86_FEATURE_CET); here and... > + if (cmdline_find_option_bool(boot_command_line, "no_user_ibt")) > + setup_clear_cpu_cap(X86_FEATURE_IBT); ... here. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette