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=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 6C975C33CB1 for ; Tue, 14 Jan 2020 10:17:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C98920678 for ; Tue, 14 Jan 2020 10:17:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732408AbgANKRs (ORCPT ); Tue, 14 Jan 2020 05:17:48 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:42350 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732190AbgANKRB (ORCPT ); Tue, 14 Jan 2020 05:17:01 -0500 Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1irJFq-0007hu-4I; Tue, 14 Jan 2020 11:16:58 +0100 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id 025C01C1928; Tue, 14 Jan 2020 11:16:55 +0100 (CET) Date: Tue, 14 Jan 2020 10:16:54 -0000 From: "tip-bot2 for Sean Christopherson" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/cpu] x86/mce: WARN once if IA32_FEAT_CTL MSR is left unlocked Cc: Sean Christopherson , Borislav Petkov , x86 , LKML In-Reply-To: <20191221044513.21680-6-sean.j.christopherson@intel.com> References: <20191221044513.21680-6-sean.j.christopherson@intel.com> MIME-Version: 1.0 Message-ID: <157899701473.1022.7710565151243359704.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/cpu branch of tip: Commit-ID: 6d527cebfa04ba4792be9e79e0d7cab22ab6c377 Gitweb: https://git.kernel.org/tip/6d527cebfa04ba4792be9e79e0d7cab22ab6c377 Author: Sean Christopherson AuthorDate: Fri, 20 Dec 2019 20:44:59 -08:00 Committer: Borislav Petkov CommitterDate: Mon, 13 Jan 2020 17:47:18 +01:00 x86/mce: WARN once if IA32_FEAT_CTL MSR is left unlocked WARN if the IA32_FEAT_CTL MSR is somehow left unlocked now that CPU initialization unconditionally locks the MSR. Signed-off-by: Sean Christopherson Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20191221044513.21680-6-sean.j.christopherson@intel.com --- arch/x86/kernel/cpu/mce/intel.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/mce/intel.c b/arch/x86/kernel/cpu/mce/intel.c index c238518..5627b10 100644 --- a/arch/x86/kernel/cpu/mce/intel.c +++ b/arch/x86/kernel/cpu/mce/intel.c @@ -116,14 +116,15 @@ static bool lmce_supported(void) /* * BIOS should indicate support for LMCE by setting bit 20 in * IA32_FEAT_CTL without which touching MCG_EXT_CTL will generate a #GP - * fault. + * fault. The MSR must also be locked for LMCE_ENABLED to take effect. + * WARN if the MSR isn't locked as init_ia32_feat_ctl() unconditionally + * locks the MSR in the event that it wasn't already locked by BIOS. */ rdmsrl(MSR_IA32_FEAT_CTL, tmp); - if ((tmp & (FEAT_CTL_LOCKED | FEAT_CTL_LMCE_ENABLED)) == - (FEAT_CTL_LOCKED | FEAT_CTL_LMCE_ENABLED)) - return true; + if (WARN_ON_ONCE(!(tmp & FEAT_CTL_LOCKED))) + return false; - return false; + return tmp & FEAT_CTL_LMCE_ENABLED; } bool mce_intel_cmci_poll(void)