Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757066AbdLVKrR (ORCPT ); Fri, 22 Dec 2017 05:47:17 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:33758 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756315AbdLVIua (ORCPT ); Fri, 22 Dec 2017 03:50:30 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andy Lutomirski , Borislav Petkov , Andrew Morton , Andrey Ryabinin , Andy Lutomirski , Borislav Petkov , Brian Gerst , Dave Hansen , Denys Vlasenko , "H. Peter Anvin" , Linus Torvalds , "Luis R. Rodriguez" , Oleg Nesterov , Peter Zijlstra , Thomas Gleixner , Toshi Kani , linux-mm@kvack.org, Ingo Molnar Subject: [PATCH 4.4 05/78] x86/mm: Add a noinvpcid boot option to turn off INVPCID Date: Fri, 22 Dec 2017 09:45:46 +0100 Message-Id: <20171222084557.425162793@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171222084556.909780563@linuxfoundation.org> References: <20171222084556.909780563@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2431 Lines: 75 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski commit d12a72b844a49d4162f24cefdab30bed3f86730e upstream. This adds a chicken bit to turn off INVPCID in case something goes wrong. It's an early_param() because we do TLB flushes before we parse __setup() parameters. Signed-off-by: Andy Lutomirski Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andrey Ryabinin Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Luis R. Rodriguez Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Toshi Kani Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/f586317ed1bc2b87aee652267e515b90051af385.1454096309.git.luto@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- Documentation/kernel-parameters.txt | 2 ++ arch/x86/kernel/cpu/common.c | 16 ++++++++++++++++ 2 files changed, 18 insertions(+) --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2519,6 +2519,8 @@ bytes respectively. Such letter suffixes nointroute [IA-64] + noinvpcid [X86] Disable the INVPCID cpu feature. + nojitter [IA-64] Disables jitter checking for ITC timers. no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -162,6 +162,22 @@ static int __init x86_mpx_setup(char *s) } __setup("nompx", x86_mpx_setup); +static int __init x86_noinvpcid_setup(char *s) +{ + /* noinvpcid doesn't accept parameters */ + if (s) + return -EINVAL; + + /* do not emit a message if the feature is not present */ + if (!boot_cpu_has(X86_FEATURE_INVPCID)) + return 0; + + setup_clear_cpu_cap(X86_FEATURE_INVPCID); + pr_info("noinvpcid: INVPCID feature disabled\n"); + return 0; +} +early_param("noinvpcid", x86_noinvpcid_setup); + #ifdef CONFIG_X86_32 static int cachesize_override = -1; static int disable_x86_serial_nr = 1;