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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 F0B02C35247 for ; Mon, 3 Feb 2020 21:43:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C904420838 for ; Mon, 3 Feb 2020 21:43:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727177AbgBCVnC (ORCPT ); Mon, 3 Feb 2020 16:43:02 -0500 Received: from mga01.intel.com ([192.55.52.88]:38302 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726928AbgBCVnB (ORCPT ); Mon, 3 Feb 2020 16:43:01 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Feb 2020 13:43:01 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,398,1574150400"; d="scan'208";a="278868982" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by FMSMGA003.fm.intel.com with ESMTP; 03 Feb 2020 13:43:01 -0800 Date: Mon, 3 Feb 2020 13:43:00 -0800 From: Sean Christopherson To: Xiaoyao Li Cc: Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, David Laight Subject: Re: [PATCH v2 5/6] kvm: x86: Emulate MSR IA32_CORE_CAPABILITIES Message-ID: <20200203214300.GI19638@linux.intel.com> References: <20200203151608.28053-1-xiaoyao.li@intel.com> <20200203151608.28053-6-xiaoyao.li@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200203151608.28053-6-xiaoyao.li@intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 03, 2020 at 11:16:07PM +0800, Xiaoyao Li wrote: > Emulate MSR_IA32_CORE_CAPABILITIES in software and unconditionally > advertise its support to userspace. Like MSR_IA32_ARCH_CAPABILITIES, it > is a feature-enumerating MSR and can be fully emulated regardless of > hardware support. Existence of CORE_CAPABILITIES is enumerated via > CPUID.(EAX=7H,ECX=0):EDX[30]. > > Note, support for individual features enumerated via CORE_CAPABILITIES, > e.g., split lock detection, will be added in future patches. > > Signed-off-by: Xiaoyao Li > --- > arch/x86/include/asm/kvm_host.h | 1 + > arch/x86/kvm/cpuid.c | 5 +++-- > arch/x86/kvm/x86.c | 22 ++++++++++++++++++++++ > 3 files changed, 26 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 329d01c689b7..dc231240102f 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -591,6 +591,7 @@ struct kvm_vcpu_arch { > u64 ia32_xss; > u64 microcode_version; > u64 arch_capabilities; > + u64 core_capabilities; > > /* > * Paging state of the vcpu > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index b1c469446b07..7282d04f3a6b 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -409,10 +409,11 @@ static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry, int index) > boot_cpu_has(X86_FEATURE_AMD_SSBD)) > entry->edx |= F(SPEC_CTRL_SSBD); > /* > - * We emulate ARCH_CAPABILITIES in software even > - * if the host doesn't support it. > + * ARCH_CAPABILITIES and CORE_CAPABILITIES are emulated in > + * software regardless of host support. > */ > entry->edx |= F(ARCH_CAPABILITIES); > + entry->edx |= F(CORE_CAPABILITIES); > break; > case 1: > entry->eax &= kvm_cpuid_7_1_eax_x86_features; > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 821b7404c0fd..a97a8f5dd1df 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -1222,6 +1222,7 @@ static const u32 emulated_msrs_all[] = { > MSR_IA32_TSC_ADJUST, > MSR_IA32_TSCDEADLINE, > MSR_IA32_ARCH_CAPABILITIES, > + MSR_IA32_CORE_CAPS, > MSR_IA32_MISC_ENABLE, > MSR_IA32_MCG_STATUS, > MSR_IA32_MCG_CTL, > @@ -1288,6 +1289,7 @@ static const u32 msr_based_features_all[] = { > MSR_F10H_DECFG, > MSR_IA32_UCODE_REV, > MSR_IA32_ARCH_CAPABILITIES, > + MSR_IA32_CORE_CAPS, > }; > > static u32 msr_based_features[ARRAY_SIZE(msr_based_features_all)]; > @@ -1341,12 +1343,20 @@ static u64 kvm_get_arch_capabilities(void) > return data; > } > > +static u64 kvm_get_core_capabilities(void) > +{ > + return 0; > +} > + > static int kvm_get_msr_feature(struct kvm_msr_entry *msr) > { > switch (msr->index) { > case MSR_IA32_ARCH_CAPABILITIES: > msr->data = kvm_get_arch_capabilities(); > break; > + case MSR_IA32_CORE_CAPS: > + msr->data = kvm_get_core_capabilities(); > + break; > case MSR_IA32_UCODE_REV: > rdmsrl_safe(msr->index, &msr->data); > break; > @@ -2716,6 +2726,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > return 1; > vcpu->arch.arch_capabilities = data; > break; > + case MSR_IA32_CORE_CAPS: > + if (!msr_info->host_initiated) Shouldn't @data be checked against kvm_get_core_capabilities()? > + return 1; > + vcpu->arch.core_capabilities = data; > + break; > case MSR_EFER: > return set_efer(vcpu, msr_info); > case MSR_K7_HWCR: > @@ -3044,6 +3059,12 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > return 1; > msr_info->data = vcpu->arch.arch_capabilities; > break; > + case MSR_IA32_CORE_CAPS: > + if (!msr_info->host_initiated && > + !guest_cpuid_has(vcpu, X86_FEATURE_CORE_CAPABILITIES)) > + return 1; > + msr_info->data = vcpu->arch.core_capabilities; > + break; > case MSR_IA32_POWER_CTL: > msr_info->data = vcpu->arch.msr_ia32_power_ctl; > break; > @@ -9288,6 +9309,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) > goto free_guest_fpu; > > vcpu->arch.arch_capabilities = kvm_get_arch_capabilities(); > + vcpu->arch.core_capabilities = kvm_get_core_capabilities(); > vcpu->arch.msr_platform_info = MSR_PLATFORM_INFO_CPUID_FAULT; > kvm_vcpu_mtrr_init(vcpu); > vcpu_load(vcpu); > -- > 2.23.0 >