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=-16.8 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 2B6F5C433E6 for ; Wed, 10 Mar 2021 22:01:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C74F564FAB for ; Wed, 10 Mar 2021 22:01:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C74F564FAB 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 0AE6C8D021C; Wed, 10 Mar 2021 17:01:19 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 03E828D021B; Wed, 10 Mar 2021 17:01:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BD2708D021D; Wed, 10 Mar 2021 17:01:18 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0147.hostedemail.com [216.40.44.147]) by kanga.kvack.org (Postfix) with ESMTP id 89E158D0219 for ; Wed, 10 Mar 2021 17:01:18 -0500 (EST) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 50E11180ACC31 for ; Wed, 10 Mar 2021 22:01:18 +0000 (UTC) X-FDA: 77905336236.19.23E66F9 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by imf10.hostedemail.com (Postfix) with ESMTP id 4C9BF4080F78 for ; Wed, 10 Mar 2021 22:01:13 +0000 (UTC) IronPort-SDR: KyQ0JGfn4/bgL4IwCGt3NB5QOykA8iYdU+24MlpU/UGtf1Wl/jCWkTmS3Nn74IKVLZ6dDI3/uc SZVwOoCyNb5A== X-IronPort-AV: E=McAfee;i="6000,8403,9919"; a="167846419" X-IronPort-AV: E=Sophos;i="5.81,238,1610438400"; d="scan'208";a="167846419" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2021 14:01:13 -0800 IronPort-SDR: z57RMzaH06ue73X5qcUVIt/i4n1wCWMRsWpWvPatwq3VNQZ0CHLtwZO3QI7x644eh6nBHhh8++ f4RffhgL17+A== X-IronPort-AV: E=Sophos;i="5.81,238,1610438400"; d="scan'208";a="403847588" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2021 14:01:13 -0800 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 v22 04/28] x86/cpufeatures: Introduce X86_FEATURE_CET and setup functions Date: Wed, 10 Mar 2021 14:00:22 -0800 Message-Id: <20210310220046.15866-5-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210310220046.15866-1-yu-cheng.yu@intel.com> References: <20210310220046.15866-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Stat-Signature: nawrgd1zwixs6at5qfb358n8ccbqh7dy X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 4C9BF4080F78 Received-SPF: none (intel.com>: No applicable sender policy available) receiver=imf10; identity=mailfrom; envelope-from=""; helo=mga12.intel.com; client-ip=192.55.52.136 X-HE-DKIM-Result: none/none X-HE-Tag: 1615413673-776149 Content-Transfer-Encoding: quoted-printable 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 a software-defined X86_FEATURE_CET, which indicates either Shad= ow Stack or Indirect Branch Tracking (or both) is present. Also introduce related cpu init/setup functions. Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook --- arch/x86/include/asm/cpufeatures.h | 2 +- arch/x86/include/asm/disabled-features.h | 5 ++++- arch/x86/include/uapi/asm/processor-flags.h | 2 ++ arch/x86/kernel/cpu/common.c | 14 ++++++++++++++ arch/x86/kernel/cpu/intel.c | 3 +++ 5 files changed, 24 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cp= ufeatures.h index bf861fc89fef..d771e62677de 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -108,7 +108,7 @@ #define X86_FEATURE_EXTD_APICID ( 3*32+26) /* Extended APICID (8 bits) = */ #define X86_FEATURE_AMD_DCM ( 3*32+27) /* AMD multi-node processor */ #define X86_FEATURE_APERFMPERF ( 3*32+28) /* P-State hardware coordinat= ion feedback capability (APERF/MPERF MSRs) */ -/* free ( 3*32+29) */ +#define X86_FEATURE_CET ( 3*32+29) /* Control-flow enforcement */ #define X86_FEATURE_NONSTOP_TSC_S3 ( 3*32+30) /* TSC doesn't stop in S3 = state */ #define X86_FEATURE_TSC_KNOWN_FREQ ( 3*32+31) /* TSC has known frequency= */ =20 diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/= asm/disabled-features.h index 914b353fe75c..b9a73b882cf9 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -71,9 +71,11 @@ #ifdef CONFIG_X86_CET #define DISABLE_SHSTK 0 #define DISABLE_IBT 0 +#define DISABLE_CET 0 #else #define DISABLE_SHSTK (1 << (X86_FEATURE_SHSTK & 31)) #define DISABLE_IBT (1 << (X86_FEATURE_IBT & 31)) +#define DISABLE_CET (1 << (X86_FEATURE_CET & 31)) #endif =20 /* @@ -82,7 +84,8 @@ #define DISABLED_MASK0 (DISABLE_VME) #define DISABLED_MASK1 0 #define DISABLED_MASK2 0 -#define DISABLED_MASK3 (DISABLE_CYRIX_ARR|DISABLE_CENTAUR_MCR|DISABLE_K6= _MTRR) +#define DISABLED_MASK3 (DISABLE_CYRIX_ARR|DISABLE_CENTAUR_MCR|DISABLE_K6= _MTRR| \ + DISABLE_CET) #define DISABLED_MASK4 (DISABLE_PCID) #define DISABLED_MASK5 0 #define DISABLED_MASK6 0 diff --git a/arch/x86/include/uapi/asm/processor-flags.h b/arch/x86/inclu= de/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) =20 /* * x86-64 Task Priority Register, CR8 diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index ab640abe26b6..6bd07727089e 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -510,6 +510,14 @@ static __init int setup_disable_pku(char *arg) __setup("nopku", setup_disable_pku); #endif /* CONFIG_X86_64 */ =20 +static __always_inline void setup_cet(struct cpuinfo_x86 *c) +{ + if (!cpu_feature_enabled(X86_FEATURE_CET)) + 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 @@ -1255,6 +1263,11 @@ static void __init cpu_parse_early_param(void) if (cmdline_find_option_bool(boot_command_line, "noxsaves")) setup_clear_cpu_cap(X86_FEATURE_XSAVES); =20 + 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 =3D cmdline_find_option(boot_command_line, "clearcpuid", arg, si= zeof(arg)); if (arglen <=3D 0) return; @@ -1594,6 +1607,7 @@ static void identify_cpu(struct cpuinfo_x86 *c) =20 x86_init_rdrand(c); setup_pku(c); + setup_cet(c); =20 /* * Clear/Set all flags overridden by options, need do it diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 0e422a544835..2e11d9555e9b 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -334,6 +334,9 @@ static void early_init_intel(struct cpuinfo_x86 *c) =20 static void bsp_init_intel(struct cpuinfo_x86 *c) { + if (cpu_has(c, X86_FEATURE_SHSTK) || cpu_has(c, X86_FEATURE_IBT)) + setup_force_cpu_cap(X86_FEATURE_CET); + resctrl_cpu_detect(c); } =20 --=20 2.21.0