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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9BF9CC433EF for ; Fri, 8 Oct 2021 11:02:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81DF960F22 for ; Fri, 8 Oct 2021 11:02:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240174AbhJHLEi (ORCPT ); Fri, 8 Oct 2021 07:04:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56164 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239954AbhJHLEg (ORCPT ); Fri, 8 Oct 2021 07:04:36 -0400 Received: from mail-pf1-x430.google.com (mail-pf1-x430.google.com [IPv6:2607:f8b0:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3166AC061570; Fri, 8 Oct 2021 04:02:41 -0700 (PDT) Received: by mail-pf1-x430.google.com with SMTP id c29so7925823pfp.2; Fri, 08 Oct 2021 04:02:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=subject:to:cc:references:from:organization:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=HZ0UMHO87j49x91nYlKX9DeZFDQ7q4eqUqMnNd1895o=; b=bqNMT1tzwQQv0g1Ep650XhgHiUPuWSF0XuYonaB74NJrJnKZEwpv11Ju+huP+rrdGq dzlqQnxZH+d6UR0UmnLomIdAOOGHbtqztn0N7LNJGLKsHt0mY3Y2SCZ32ZLyfXU0Hqs4 n6ycqJYLdovK22FL1DBUAo1AXLXwbzOpaQzWW9nDKpl+/MGGKqPQrvAnxXMg602p5uHs NvprEZC/WHDteeUhJh2bO1ftlpWJRUkQR/JwXiREgjnn4ddoKqpaU79FVJ5BECoLYj1d rDsF5y211e0LRiUuEV1bpN0tgyU1RG4QCbu36QUnHjWe8Q6dKupYqWz/C5sIkxq7XjsI 0ahw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=HZ0UMHO87j49x91nYlKX9DeZFDQ7q4eqUqMnNd1895o=; b=RF693BTv7SuOZm/mo9BlQD16TGh91FyZf3Z/R9G27zIRSCcWLfHQZGMIejgQjaW/7r /BDzHpygnKdiM9eTzMmegftk4Qqab2B0SnYoff9LAxXtU27tqzcuvYeRKFCZRoygk0mb smXksI6AzIwA4dQ4fSsAjkrmo2VNFw311WDNAFyS9kAA3ZmRkDeRcTZTIuc8mOcm2qFZ TbeZbelw20S2DmQR0p7PwXslz7IrpdNT/LiqYisKJx6EB0fRNkSazboN4+sDFlFABwvM l4g/4ZpdjF1raJ4LyGXCCeHdd4maeQFBoqNlmPgt9iTZULyLXLkJm+yhFCE6R9mnBbRO Sy1w== X-Gm-Message-State: AOAM531PltEsgx+zcaCB+fDE7Nlo3O0pm5ItVFpgaelUrtTPnZgsKh4U gu78xT0cEVXiG+PINK514so= X-Google-Smtp-Source: ABdhPJy4iAY5CM/1Kdeb/0UKFrsJpAYaAdRPrWuxU8iJsRE8CVZDpw6RHlQJLdDXa/nh8OcrxvPyBQ== X-Received: by 2002:a62:1786:0:b0:445:1a9c:952a with SMTP id 128-20020a621786000000b004451a9c952amr9828321pfx.39.1633690960659; Fri, 08 Oct 2021 04:02:40 -0700 (PDT) Received: from Likes-MacBook-Pro.local ([103.7.29.32]) by smtp.gmail.com with ESMTPSA id x21sm2336927pfa.186.2021.10.08.04.02.37 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 08 Oct 2021 04:02:40 -0700 (PDT) Subject: Re: [PATCH 2/3] KVM: vPMU: Fill get_msr MSR_CORE_PERF_GLOBAL_OVF_CTRL w/ 0 To: Wanpeng Li Cc: Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, "linux-kernel@vger.kernel.org" , Andi Kleen References: <1633687054-18865-1-git-send-email-wanpengli@tencent.com> <1633687054-18865-2-git-send-email-wanpengli@tencent.com> From: Like Xu Organization: Tencent Message-ID: <58d59149-669f-7990-4f68-05b32ed693b5@gmail.com> Date: Fri, 8 Oct 2021 19:02:31 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <1633687054-18865-2-git-send-email-wanpengli@tencent.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org cc Andi, On 8/10/2021 5:57 pm, Wanpeng Li wrote: > From: Wanpeng Li > > SDM section 18.2.3 mentioned that: > > "IA32_PERF_GLOBAL_OVF_CTL MSR allows software to clear overflow indicator(s) of > any general-purpose or fixed-function counters via a single WRMSR." > > It is R/W mentioned by SDM, we read this msr on bare-metal during perf testing, > the value is always 0 for CLX/SKX boxes on hands. Let's fill get_msr > MSR_CORE_PERF_GLOBAL_OVF_CTRL w/ 0 as hardware behavior. > > Signed-off-by: Wanpeng Li > --- > Btw, xen also fills get_msr MSR_CORE_PERF_GLOBAL_OVF_CTRL 0. > > arch/x86/kvm/vmx/pmu_intel.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c > index 10cc4f65c4ef..47260a8563f9 100644 > --- a/arch/x86/kvm/vmx/pmu_intel.c > +++ b/arch/x86/kvm/vmx/pmu_intel.c > @@ -365,7 +365,7 @@ static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > msr_info->data = pmu->global_ctrl; > return 0; > case MSR_CORE_PERF_GLOBAL_OVF_CTRL: > - msr_info->data = pmu->global_ovf_ctrl; > + msr_info->data = 0; Tested-by: Like Xu Further, better to drop 'u64 global_ovf_ctrl' directly. > return 0; > default: > if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) || >