From patchwork Thu Nov 28 01:40:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11265185 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BF600921 for ; Thu, 28 Nov 2019 01:41:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A88EE215A5 for ; Thu, 28 Nov 2019 01:41:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728095AbfK1Blq (ORCPT ); Wed, 27 Nov 2019 20:41:46 -0500 Received: from mga02.intel.com ([134.134.136.20]:10957 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727644AbfK1BkX (ORCPT ); Wed, 27 Nov 2019 20:40:23 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 27 Nov 2019 17:40:19 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,251,1571727600"; d="scan'208";a="221166489" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.41]) by orsmga002.jf.intel.com with ESMTP; 27 Nov 2019 17:40:19 -0800 From: Sean Christopherson To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org Cc: "H. Peter Anvin" , Peter Zijlstra , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Tony Luck , Tony W Wang-oc , Len Brown , Shuah Khan , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-edac@vger.kernel.org, linux-pm@vger.kernel.org, linux-kselftest@vger.kernel.org, Borislav Petkov , Jarkko Sakkinen Subject: [PATCH v4 08/19] x86/cpu: Clear VMX feature flag if VMX is not fully enabled Date: Wed, 27 Nov 2019 17:40:05 -0800 Message-Id: <20191128014016.4389-9-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191128014016.4389-1-sean.j.christopherson@intel.com> References: <20191128014016.4389-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Now that IA32_FEAT_CTL is always configured and locked for CPUs that are known to support VMX[*], clear the VMX capability flag if the MSR is unsupported or BIOS disabled VMX, i.e. locked IA32_FEAT_CTL and didn't set the appropriate VMX enable bit. [*] Because init_ia32_feat_ctl() is called from vendors ->c_init(), it's still possible for IA32_FEAT_CTL to be left unlocked when VMX is supported by the CPU. This is not fatal, and will be addressed in a future patch. Signed-off-by: Sean Christopherson --- arch/x86/kernel/cpu/feat_ctl.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/feat_ctl.c b/arch/x86/kernel/cpu/feat_ctl.c index c4f8f767853b..a46c9e46f937 100644 --- a/arch/x86/kernel/cpu/feat_ctl.c +++ b/arch/x86/kernel/cpu/feat_ctl.c @@ -5,15 +5,21 @@ #include #include +#undef pr_fmt +#define pr_fmt(fmt) "x86/cpu: " fmt + void init_ia32_feat_ctl(struct cpuinfo_x86 *c) { + bool tboot = tboot_enabled(); u64 msr; - if (rdmsrl_safe(MSR_IA32_FEAT_CTL, &msr)) + if (rdmsrl_safe(MSR_IA32_FEAT_CTL, &msr)) { + clear_cpu_cap(c, X86_FEATURE_VMX); return; + } if (msr & FEAT_CTL_LOCKED) - return; + goto update_caps; /* * Ignore whatever value BIOS left in the MSR to avoid enabling random @@ -29,9 +35,20 @@ void init_ia32_feat_ctl(struct cpuinfo_x86 *c) if (cpu_has(c, X86_FEATURE_VMX) && IS_ENABLED(CONFIG_KVM_INTEL)) { msr |= FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX; - if (tboot_enabled()) + if (tboot) msr |= FEAT_CTL_VMX_ENABLED_INSIDE_SMX; } wrmsrl(MSR_IA32_FEAT_CTL, msr); + +update_caps: + if (!cpu_has(c, X86_FEATURE_VMX)) + return; + + if ( (tboot && !(msr & FEAT_CTL_VMX_ENABLED_INSIDE_SMX)) || + (!tboot && !(msr & FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX))) { + pr_err_once("VMX (%s TXT) disabled by BIOS\n", + tboot ? "inside" : "outside"); + clear_cpu_cap(c, X86_FEATURE_VMX); + } }