From patchwork Fri Aug 6 13:37:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhu, Lingshan" X-Patchwork-Id: 12423471 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 CCB9DC432BE for ; Fri, 6 Aug 2021 13:38:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B1A6461104 for ; Fri, 6 Aug 2021 13:38:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344186AbhHFNjN (ORCPT ); Fri, 6 Aug 2021 09:39:13 -0400 Received: from mga18.intel.com ([134.134.136.126]:16714 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344218AbhHFNjD (ORCPT ); Fri, 6 Aug 2021 09:39:03 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10068"; a="201553549" X-IronPort-AV: E=Sophos;i="5.84,300,1620716400"; d="scan'208";a="201553549" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Aug 2021 06:38:45 -0700 X-IronPort-AV: E=Sophos;i="5.84,300,1620716400"; d="scan'208";a="523463432" Received: from vmm_a4_icx.sh.intel.com (HELO localhost.localdomain) ([10.239.53.245]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Aug 2021 06:38:39 -0700 From: Zhu Lingshan To: peterz@infradead.org, pbonzini@redhat.com Cc: bp@alien8.de, seanjc@google.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, kan.liang@linux.intel.com, ak@linux.intel.com, wei.w.wang@intel.com, eranian@google.com, liuxiangdong5@huawei.com, linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org, like.xu.linux@gmail.com, boris.ostrvsky@oracle.com, Like Xu , Yao Yuan , Venkatesh Srinivas , Zhu Lingshan Subject: [PATCH V10 05/18] KVM: x86/pmu: Set MSR_IA32_MISC_ENABLE_EMON bit when vPMU is enabled Date: Fri, 6 Aug 2021 21:37:49 +0800 Message-Id: <20210806133802.3528-6-lingshan.zhu@intel.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210806133802.3528-1-lingshan.zhu@intel.com> References: <20210806133802.3528-1-lingshan.zhu@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Like Xu On Intel platforms, the software can use the IA32_MISC_ENABLE[7] bit to detect whether the processor supports performance monitoring facility. It depends on the PMU is enabled for the guest, and a software write operation to this available bit will be ignored. The proposal to ignore the toggle in KVM is the way to go and that behavior matches bare metal. Cc: Yao Yuan Signed-off-by: Like Xu Reviewed-by: Venkatesh Srinivas Signed-off-by: Zhu Lingshan Acked-by: Peter Zijlstra (Intel) --- arch/x86/kvm/vmx/pmu_intel.c | 1 + arch/x86/kvm/x86.c | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index 9efc1a6b8693..d9dbebe03cae 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -488,6 +488,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu) if (!pmu->version) return; + vcpu->arch.ia32_misc_enable_msr |= MSR_IA32_MISC_ENABLE_EMON; perf_get_x86_pmu_capability(&x86_pmu); pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index efd11702465c..f6b6984e26ef 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3321,6 +3321,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) } break; case MSR_IA32_MISC_ENABLE: + data &= ~MSR_IA32_MISC_ENABLE_EMON; if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT) && ((vcpu->arch.ia32_misc_enable_msr ^ data) & MSR_IA32_MISC_ENABLE_MWAIT)) { if (!guest_cpuid_has(vcpu, X86_FEATURE_XMM3))