From patchwork Fri May 21 22:11:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12273867 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 F404EC4707A for ; Fri, 21 May 2021 22:13:11 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9377F613F3 for ; Fri, 21 May 2021 22:13:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9377F613F3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 390238E004C; Fri, 21 May 2021 18:13:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 346688E0048; Fri, 21 May 2021 18:13:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 008638E004C; Fri, 21 May 2021 18:13:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0001.hostedemail.com [216.40.44.1]) by kanga.kvack.org (Postfix) with ESMTP id B995B8E004A for ; Fri, 21 May 2021 18:13:09 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 41C98181AF5C7 for ; Fri, 21 May 2021 22:13:09 +0000 (UTC) X-FDA: 78166639698.20.DE586F5 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by imf18.hostedemail.com (Postfix) with ESMTP id D12FD20007FD for ; Fri, 21 May 2021 22:13:05 +0000 (UTC) IronPort-SDR: fSssyN98ia7i02LZbUDwTZ6JdxSUg2IVdv84lys65WafSE4jp/R8v2Q8tfU0CrzQq2BMNeLx+I 1CFWmLhvwEJQ== X-IronPort-AV: E=McAfee;i="6200,9189,9991"; a="287123961" X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="287123961" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 May 2021 15:13:06 -0700 IronPort-SDR: cRMRLuF1oPEbeod78Vu2IkkjDxUO3/6r6iKHR/GdU0RnKfF1j5wf1QdlRXfhiUU4cRzM7O5cDy 8NqWJhp4jcgQ== X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="441116115" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 May 2021 15:13:06 -0700 From: Yu-cheng Yu To: 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 , Borislav Petkov , 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 , Haitao Huang Cc: Yu-cheng Yu Subject: [PATCH v27 04/31] x86/cpufeatures: Introduce CPU setup and option parsing for CET Date: Fri, 21 May 2021 15:11:44 -0700 Message-Id: <20210521221211.29077-5-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210521221211.29077-1-yu-cheng.yu@intel.com> References: <20210521221211.29077-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: D12FD20007FD Authentication-Results: imf18.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf18.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 192.55.52.43) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam04 X-Stat-Signature: 4kehrb1mbe9imo41njfzut3qxyjh8p9m X-HE-Tag: 1621635185-819874 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Introduce CPU setup and boot option parsing for CET features. Signed-off-by: Yu-cheng Yu Cc: Kees Cook --- v25: - Remove software-defined X86_FEATURE_CET. v24: - Update #ifdef placement to reflect Kconfig changes of splitting shadow stack and ibt. arch/x86/include/uapi/asm/processor-flags.h | 2 ++ arch/x86/kernel/cpu/common.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/arch/x86/include/uapi/asm/processor-flags.h b/arch/x86/include/uapi/asm/processor-flags.h index bcba3c643e63..a8df907e8017 100644 --- a/arch/x86/include/uapi/asm/processor-flags.h +++ b/arch/x86/include/uapi/asm/processor-flags.h @@ -130,6 +130,8 @@ #define X86_CR4_SMAP _BITUL(X86_CR4_SMAP_BIT) #define X86_CR4_PKE_BIT 22 /* enable Protection Keys support */ #define X86_CR4_PKE _BITUL(X86_CR4_PKE_BIT) +#define X86_CR4_CET_BIT 23 /* enable Control-flow Enforcement */ +#define X86_CR4_CET _BITUL(X86_CR4_CET_BIT) /* * x86-64 Task Priority Register, CR8 diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index a1b756c49a93..2612499b739e 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -509,6 +509,14 @@ static __init int setup_disable_pku(char *arg) __setup("nopku", setup_disable_pku); #endif /* CONFIG_X86_64 */ +static __always_inline void setup_cet(struct cpuinfo_x86 *c) +{ + if (!cpu_feature_enabled(X86_FEATURE_SHSTK)) + return; + + cr4_set_bits(X86_CR4_CET); +} + /* * Some CPU features depend on higher CPUID levels, which may not always * be available due to CPUID level capping or broken virtualization @@ -1253,6 +1261,11 @@ static void __init cpu_parse_early_param(void) if (cmdline_find_option_bool(boot_command_line, "noxsaves")) setup_clear_cpu_cap(X86_FEATURE_XSAVES); + if (cmdline_find_option_bool(boot_command_line, "no_user_shstk")) + setup_clear_cpu_cap(X86_FEATURE_SHSTK); + if (cmdline_find_option_bool(boot_command_line, "no_user_ibt")) + setup_clear_cpu_cap(X86_FEATURE_IBT); + arglen = cmdline_find_option(boot_command_line, "clearcpuid", arg, sizeof(arg)); if (arglen <= 0) return; @@ -1592,6 +1605,7 @@ static void identify_cpu(struct cpuinfo_x86 *c) x86_init_rdrand(c); setup_pku(c); + setup_cet(c); /* * Clear/Set all flags overridden by options, need do it