From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753034AbdF2PzB (ORCPT ); Thu, 29 Jun 2017 11:55:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:49240 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752520AbdF2Pxg (ORCPT ); Thu, 29 Jun 2017 11:53:36 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E51822BE2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=luto@kernel.org From: Andy Lutomirski To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov , Linus Torvalds , Andrew Morton , Mel Gorman , "linux-mm@kvack.org" , Nadav Amit , Rik van Riel , Dave Hansen , Arjan van de Ven , Peter Zijlstra , Andy Lutomirski Subject: [PATCH v4 07/10] x86/mm: Disable PCID on 32-bit kernels Date: Thu, 29 Jun 2017 08:53:19 -0700 Message-Id: <2e391769192a4d31b808410c383c6bf0734bc6ea.1498751203.git.luto@kernel.org> X-Mailer: git-send-email 2.9.4 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 32-bit kernels on new hardware will see PCID in CPUID, but PCID can only be used in 64-bit mode. Rather than making all PCID code conditional, just disable the feature on 32-bit builds. Reviewed-by: Nadav Amit Reviewed-by: Borislav Petkov Reviewed-by: Thomas Gleixner Signed-off-by: Andy Lutomirski --- arch/x86/include/asm/disabled-features.h | 4 +++- arch/x86/kernel/cpu/bugs.c | 8 ++++++++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index 5dff775af7cd..c10c9128f54e 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -21,11 +21,13 @@ # define DISABLE_K6_MTRR (1<<(X86_FEATURE_K6_MTRR & 31)) # define DISABLE_CYRIX_ARR (1<<(X86_FEATURE_CYRIX_ARR & 31)) # define DISABLE_CENTAUR_MCR (1<<(X86_FEATURE_CENTAUR_MCR & 31)) +# define DISABLE_PCID 0 #else # define DISABLE_VME 0 # define DISABLE_K6_MTRR 0 # define DISABLE_CYRIX_ARR 0 # define DISABLE_CENTAUR_MCR 0 +# define DISABLE_PCID (1<<(X86_FEATURE_PCID & 31)) #endif /* CONFIG_X86_64 */ #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS @@ -49,7 +51,7 @@ #define DISABLED_MASK1 0 #define DISABLED_MASK2 0 #define DISABLED_MASK3 (DISABLE_CYRIX_ARR|DISABLE_CENTAUR_MCR|DISABLE_K6_MTRR) -#define DISABLED_MASK4 0 +#define DISABLED_MASK4 (DISABLE_PCID) #define DISABLED_MASK5 0 #define DISABLED_MASK6 0 #define DISABLED_MASK7 0 diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 0af86d9242da..db684880d74a 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -21,6 +21,14 @@ void __init check_bugs(void) { +#ifdef CONFIG_X86_32 + /* + * Regardless of whether PCID is enumerated, the SDM says + * that it can't be enabled in 32-bit mode. + */ + setup_clear_cpu_cap(X86_FEATURE_PCID); +#endif + identify_boot_cpu(); if (!IS_ENABLED(CONFIG_SMP)) { -- 2.9.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f70.google.com (mail-oi0-f70.google.com [209.85.218.70]) by kanga.kvack.org (Postfix) with ESMTP id 47A2D6B036A for ; Thu, 29 Jun 2017 11:53:37 -0400 (EDT) Received: by mail-oi0-f70.google.com with SMTP id t187so22044589oie.3 for ; Thu, 29 Jun 2017 08:53:37 -0700 (PDT) Received: from mail.kernel.org (mail.kernel.org. [198.145.29.99]) by mx.google.com with ESMTPS id q187si1106167oih.222.2017.06.29.08.53.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 29 Jun 2017 08:53:36 -0700 (PDT) From: Andy Lutomirski Subject: [PATCH v4 07/10] x86/mm: Disable PCID on 32-bit kernels Date: Thu, 29 Jun 2017 08:53:19 -0700 Message-Id: <2e391769192a4d31b808410c383c6bf0734bc6ea.1498751203.git.luto@kernel.org> In-Reply-To: References: In-Reply-To: References: Sender: owner-linux-mm@kvack.org List-ID: To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov , Linus Torvalds , Andrew Morton , Mel Gorman , "linux-mm@kvack.org" , Nadav Amit , Rik van Riel , Dave Hansen , Arjan van de Ven , Peter Zijlstra , Andy Lutomirski 32-bit kernels on new hardware will see PCID in CPUID, but PCID can only be used in 64-bit mode. Rather than making all PCID code conditional, just disable the feature on 32-bit builds. Reviewed-by: Nadav Amit Reviewed-by: Borislav Petkov Reviewed-by: Thomas Gleixner Signed-off-by: Andy Lutomirski --- arch/x86/include/asm/disabled-features.h | 4 +++- arch/x86/kernel/cpu/bugs.c | 8 ++++++++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index 5dff775af7cd..c10c9128f54e 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -21,11 +21,13 @@ # define DISABLE_K6_MTRR (1<<(X86_FEATURE_K6_MTRR & 31)) # define DISABLE_CYRIX_ARR (1<<(X86_FEATURE_CYRIX_ARR & 31)) # define DISABLE_CENTAUR_MCR (1<<(X86_FEATURE_CENTAUR_MCR & 31)) +# define DISABLE_PCID 0 #else # define DISABLE_VME 0 # define DISABLE_K6_MTRR 0 # define DISABLE_CYRIX_ARR 0 # define DISABLE_CENTAUR_MCR 0 +# define DISABLE_PCID (1<<(X86_FEATURE_PCID & 31)) #endif /* CONFIG_X86_64 */ #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS @@ -49,7 +51,7 @@ #define DISABLED_MASK1 0 #define DISABLED_MASK2 0 #define DISABLED_MASK3 (DISABLE_CYRIX_ARR|DISABLE_CENTAUR_MCR|DISABLE_K6_MTRR) -#define DISABLED_MASK4 0 +#define DISABLED_MASK4 (DISABLE_PCID) #define DISABLED_MASK5 0 #define DISABLED_MASK6 0 #define DISABLED_MASK7 0 diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 0af86d9242da..db684880d74a 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -21,6 +21,14 @@ void __init check_bugs(void) { +#ifdef CONFIG_X86_32 + /* + * Regardless of whether PCID is enumerated, the SDM says + * that it can't be enabled in 32-bit mode. + */ + setup_clear_cpu_cap(X86_FEATURE_PCID); +#endif + identify_boot_cpu(); if (!IS_ENABLED(CONFIG_SMP)) { -- 2.9.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org