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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 E8909C43441 for ; Mon, 19 Nov 2018 21:54:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AE49020989 for ; Mon, 19 Nov 2018 21:54:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AE49020989 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731722AbeKTIUg (ORCPT ); Tue, 20 Nov 2018 03:20:36 -0500 Received: from mga09.intel.com ([134.134.136.24]:32114 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731297AbeKTIUf (ORCPT ); Tue, 20 Nov 2018 03:20:35 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Nov 2018 13:54:55 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,254,1539673200"; d="scan'208";a="92423885" Received: from yyu32-desk1.sc.intel.com ([143.183.136.147]) by orsmga006.jf.intel.com with ESMTP; 19 Nov 2018 13:54:54 -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 , 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 Cc: Yu-cheng Yu Subject: [RFC PATCH v6 02/11] x86/cet/ibt: User-mode indirect branch tracking support Date: Mon, 19 Nov 2018 13:49:25 -0800 Message-Id: <20181119214934.6174-3-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181119214934.6174-1-yu-cheng.yu@intel.com> References: <20181119214934.6174-1-yu-cheng.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add user-mode indirect branch tracking enabling/disabling and supporting routines. Signed-off-by: H.J. Lu Signed-off-by: Yu-cheng Yu --- arch/x86/include/asm/cet.h | 7 +++++ arch/x86/include/asm/disabled-features.h | 8 ++++- arch/x86/kernel/cet.c | 31 +++++++++++++++++++ arch/x86/kernel/cpu/common.c | 17 ++++++++++ arch/x86/kernel/process.c | 1 + .../arch/x86/include/asm/disabled-features.h | 8 ++++- 6 files changed, 70 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/cet.h b/arch/x86/include/asm/cet.h index 29d88e4d8d5d..810d3e386fdb 100644 --- a/arch/x86/include/asm/cet.h +++ b/arch/x86/include/asm/cet.h @@ -12,8 +12,11 @@ struct task_struct; struct cet_status { unsigned long shstk_base; unsigned long shstk_size; + unsigned long ibt_bitmap_addr; + unsigned long ibt_bitmap_size; unsigned int locked:1; unsigned int shstk_enabled:1; + unsigned int ibt_enabled:1; }; #ifdef CONFIG_X86_INTEL_CET @@ -25,6 +28,8 @@ void cet_disable_shstk(void); void cet_disable_free_shstk(struct task_struct *p); int cet_restore_signal(unsigned long ssp); int cet_setup_signal(bool ia32, unsigned long rstor, unsigned long *new_ssp); +int cet_setup_ibt(void); +void cet_disable_ibt(void); #else static inline int prctl_cet(int option, unsigned long arg2) { return -EINVAL; } static inline int cet_setup_shstk(void) { return -EINVAL; } @@ -35,6 +40,8 @@ static inline void cet_disable_free_shstk(struct task_struct *p) {} static inline int cet_restore_signal(unsigned long ssp) { return -EINVAL; } static inline int cet_setup_signal(bool ia32, unsigned long rstor, unsigned long *new_ssp) { return -EINVAL; } +static inline int cet_setup_ibt(void) { return -EINVAL; } +static inline void cet_disable_ibt(void) {} #endif #define cpu_x86_cet_enabled() \ diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index 3624a11e5ba6..ce5bdaf0f1ff 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -62,6 +62,12 @@ #define DISABLE_SHSTK (1<<(X86_FEATURE_SHSTK & 31)) #endif +#ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER +#define DISABLE_IBT 0 +#else +#define DISABLE_IBT (1<<(X86_FEATURE_IBT & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -72,7 +78,7 @@ #define DISABLED_MASK4 (DISABLE_PCID) #define DISABLED_MASK5 0 #define DISABLED_MASK6 0 -#define DISABLED_MASK7 (DISABLE_PTI) +#define DISABLED_MASK7 (DISABLE_PTI|DISABLE_IBT) #define DISABLED_MASK8 0 #define DISABLED_MASK9 (DISABLE_MPX) #define DISABLED_MASK10 0 diff --git a/arch/x86/kernel/cet.c b/arch/x86/kernel/cet.c index 1b5d1ce4df8f..fd157a6208c3 100644 --- a/arch/x86/kernel/cet.c +++ b/arch/x86/kernel/cet.c @@ -13,6 +13,8 @@ #include #include #include +#include +#include #include #include #include @@ -302,3 +304,32 @@ int cet_setup_signal(bool ia32, unsigned long rstor_addr, set_shstk_ptr(ssp); return 0; } + +int cet_setup_ibt(void) +{ + u64 r; + + if (!cpu_feature_enabled(X86_FEATURE_IBT)) + return -EOPNOTSUPP; + + rdmsrl(MSR_IA32_U_CET, r); + r |= (MSR_IA32_CET_ENDBR_EN | MSR_IA32_CET_NO_TRACK_EN); + wrmsrl(MSR_IA32_U_CET, r); + + current->thread.cet.ibt_enabled = 1; + return 0; +} + +void cet_disable_ibt(void) +{ + u64 r; + + if (!cpu_feature_enabled(X86_FEATURE_IBT)) + return; + + rdmsrl(MSR_IA32_U_CET, r); + r &= ~(MSR_IA32_CET_ENDBR_EN | MSR_IA32_CET_LEG_IW_EN | + MSR_IA32_CET_NO_TRACK_EN | MSR_IA32_CET_BITMAP_MASK); + wrmsrl(MSR_IA32_U_CET, r); + current->thread.cet.ibt_enabled = 0; +} diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 795e195bf2fe..16bcc85d3819 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -435,6 +435,23 @@ static __init int setup_disable_shstk(char *s) __setup("no_cet_shstk", setup_disable_shstk); #endif +#ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER +static __init int setup_disable_ibt(char *s) +{ + /* require an exact match without trailing characters */ + if (s[0] != '\0') + return 0; + + if (!boot_cpu_has(X86_FEATURE_IBT)) + return 1; + + setup_clear_cpu_cap(X86_FEATURE_IBT); + pr_info("x86: 'no_cet_ibt' specified, disabling Branch Tracking\n"); + return 1; +} +__setup("no_cet_ibt", setup_disable_ibt); +#endif + /* * Some CPU features depend on higher CPUID levels, which may not always * be available due to CPUID level capping or broken virtualization diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index f240fce2b20f..f44c26bf6d28 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -137,6 +137,7 @@ void flush_thread(void) memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); cet_disable_shstk(); + cet_disable_ibt(); fpu__clear(&tsk->thread.fpu); } diff --git a/tools/arch/x86/include/asm/disabled-features.h b/tools/arch/x86/include/asm/disabled-features.h index 3624a11e5ba6..ce5bdaf0f1ff 100644 --- a/tools/arch/x86/include/asm/disabled-features.h +++ b/tools/arch/x86/include/asm/disabled-features.h @@ -62,6 +62,12 @@ #define DISABLE_SHSTK (1<<(X86_FEATURE_SHSTK & 31)) #endif +#ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER +#define DISABLE_IBT 0 +#else +#define DISABLE_IBT (1<<(X86_FEATURE_IBT & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -72,7 +78,7 @@ #define DISABLED_MASK4 (DISABLE_PCID) #define DISABLED_MASK5 0 #define DISABLED_MASK6 0 -#define DISABLED_MASK7 (DISABLE_PTI) +#define DISABLED_MASK7 (DISABLE_PTI|DISABLE_IBT) #define DISABLED_MASK8 0 #define DISABLED_MASK9 (DISABLE_MPX) #define DISABLED_MASK10 0 -- 2.17.1