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 769FAC35DF9 for ; Thu, 27 Feb 2020 18:08:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AFFD2468E for ; Thu, 27 Feb 2020 18:08:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729843AbgB0SIC (ORCPT ); Thu, 27 Feb 2020 13:08:02 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:35032 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729142AbgB0SIC (ORCPT ); Thu, 27 Feb 2020 13:08:02 -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 1j7NZf-0002LJ-8H; Thu, 27 Feb 2020 19:07:51 +0100 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id CBF161C2172; Thu, 27 Feb 2020 19:07:50 +0100 (CET) Date: Thu, 27 Feb 2020 18:07:50 -0000 From: "tip-bot2 for Sean Christopherson" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/urgent] x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes Cc: Jacob Keller , Sean Christopherson , Borislav Petkov , Dave Hansen , stable@vger.kernel.org, x86 , LKML In-Reply-To: <20200226231615.13664-1-sean.j.christopherson@intel.com> References: <20200226231615.13664-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Message-ID: <158282687050.28353.6531125831614540420.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/urgent branch of tip: Commit-ID: 735a6dd02222d8d070c7bb748f25895239ca8c92 Gitweb: https://git.kernel.org/tip/735a6dd02222d8d070c7bb748f25895239ca8c92 Author: Sean Christopherson AuthorDate: Wed, 26 Feb 2020 15:16:15 -08:00 Committer: Borislav Petkov CommitterDate: Thu, 27 Feb 2020 19:02:45 +01:00 x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes Explicitly set X86_FEATURE_OSPKE via set_cpu_cap() instead of calling get_cpu_cap() to pull the feature bit from CPUID after enabling CR4.PKE. Invoking get_cpu_cap() effectively wipes out any {set,clear}_cpu_cap() changes that were made between this_cpu->c_init() and setup_pku(), as all non-synthetic feature words are reinitialized from the CPU's CPUID values. Blasting away capability updates manifests most visibility when running on a VMX capable CPU, but with VMX disabled by BIOS. To indicate that VMX is disabled, init_ia32_feat_ctl() clears X86_FEATURE_VMX, using clear_cpu_cap() instead of setup_clear_cpu_cap() so that KVM can report which CPU is misconfigured (KVM needs to probe every CPU anyways). Restoring X86_FEATURE_VMX from CPUID causes KVM to think VMX is enabled, ultimately leading to an unexpected #GP when KVM attempts to do VMXON. Arguably, init_ia32_feat_ctl() should use setup_clear_cpu_cap() and let KVM figure out a different way to report the misconfigured CPU, but VMX is not the only feature bit that is affected, i.e. there is precedent that tweaking feature bits via {set,clear}_cpu_cap() after ->c_init() is expected to work. Most notably, x86_init_rdrand()'s clearing of X86_FEATURE_RDRAND when RDRAND malfunctions is also overwritten. Fixes: 0697694564c8 ("x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU") Reported-by: Jacob Keller Signed-off-by: Sean Christopherson Signed-off-by: Borislav Petkov Acked-by: Dave Hansen Tested-by: Jacob Keller Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200226231615.13664-1-sean.j.christopherson@intel.com --- arch/x86/kernel/cpu/common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 52c9bfb..4cdb123 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -445,7 +445,7 @@ static __always_inline void setup_pku(struct cpuinfo_x86 *c) * cpuid bit to be set. We need to ensure that we * update that bit in this CPU's "cpu_info". */ - get_cpu_cap(c); + set_cpu_cap(c, X86_FEATURE_OSPKE); } #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS