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=-14.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 9CFA8C432BE for ; Mon, 9 Aug 2021 05:08:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A43C60F9F for ; Mon, 9 Aug 2021 05:08:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233104AbhHIFJE (ORCPT ); Mon, 9 Aug 2021 01:09:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229516AbhHIFJC (ORCPT ); Mon, 9 Aug 2021 01:09:02 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E0D1C061764; Sun, 8 Aug 2021 22:08:41 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id e2-20020a17090a4a02b029016f3020d867so28340476pjh.3; Sun, 08 Aug 2021 22:08:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:references:cc:from:organization:subject:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=nVRGhQ52gBWFp8QzDfKqSErmQkgn6uw1EtmTvvUH/SY=; b=e/yZ/TMUZPTcvotOAgjOYPIM/hwMDno3wL9N3tdWkVzKO0aHZgbRyJfcTZ35UMoP3w +UR9WOhqUIL0pYSZRQseUJ/noVCsuKe4t8pxgeGUmFFbkutLlFe79UMD61ajjm1vhj/1 Nr42kS9dld/jSa43z+R+or2PFHDjNaYJbCSslpKem4Y/c4vY3gV/jPv+zvlSMOpjqI3I Et7DFEtdwvBLDlf+8uki8Jo9womWI+oaLnwDTxCYh+I0WpnictBPWE6i4DWW6cG7vAid nFUDwKmI0bu/bmvkWXh9aXVaLJTvp5sqNslbrdkBKpK06JdyU2RYHaOw7O54QaSqNO8Y O61w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:references:cc:from:organization:subject :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=nVRGhQ52gBWFp8QzDfKqSErmQkgn6uw1EtmTvvUH/SY=; b=gJk1WN28nht/txO++OD+B2T/qmkq9WYUHG1hj3MyE7geVgKBZhVt2is4gEc2F0lkIo lIu/tx8f5jm+wsSLi+GX0gxrMvBun7U4QcxKAA/DKM8WR5YGZ8OoWf13rxudtM2fI1oU QI+2xf/SmLjumRxRTb58cYeMGsn3JH12d/AED7m5AWof2fzfeBXtddGiiB+TUrQkoHX5 eI/56FjcQrJvM8Z2jHyda8y/8Keek+PcK9yrSp6hbuDonywbUerdeZLPsCxtAtk5V00L eSyCd+f3ckSSJla7w4kIiRqeHM0jU1RxAsfv7W6HfW05IfHrpgAVExdevg6Xj1AD/mHM +v5A== X-Gm-Message-State: AOAM531a+8hhoC3BC8ZgQyHnhEWUs7ZBa3PkJEK2lV7Nsu4UzH9+4cOa UB01t3wdOPBYAq03z/pO3DCeqaHrO3WdlA== X-Google-Smtp-Source: ABdhPJxzbPTQkCEN+KHiTTz0ubUlJNCzsj6VQp9gW/z3RN3y6ao8d6VMyPtILOc+ar8YyoZWf8EAtQ== X-Received: by 2002:a17:902:b193:b029:11a:a179:453a with SMTP id s19-20020a170902b193b029011aa179453amr18858372plr.69.1628485721186; Sun, 08 Aug 2021 22:08:41 -0700 (PDT) Received: from Likes-MacBook-Pro.local ([103.7.29.32]) by smtp.gmail.com with ESMTPSA id u129sm18989065pfc.59.2021.08.08.22.08.38 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 08 Aug 2021 22:08:40 -0700 (PDT) To: Yang Weijiang References: <1628235745-26566-1-git-send-email-weijiang.yang@intel.com> <1628235745-26566-14-git-send-email-weijiang.yang@intel.com> Cc: pbonzini@redhat.com, jmattson@google.com, seanjc@google.com, vkuznets@redhat.com, wei.w.wang@intel.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org From: Like Xu Organization: Tencent Subject: Re: [PATCH v7 13/15] KVM: x86/vmx: Clear Arch LBREn bit before inject #DB to guest Message-ID: Date: Mon, 9 Aug 2021 13:08:32 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <1628235745-26566-14-git-send-email-weijiang.yang@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/8/2021 3:42 pm, Yang Weijiang wrote: > Per ISA spec, need to clear the bit before inject #DB. Please paste the SDM statement accurately so that the reviewers can verify that the code is consistent with the documentation. > > Signed-off-by: Yang Weijiang > --- > arch/x86/kvm/vmx/vmx.c | 21 +++++++++++++++++++++ > 1 file changed, 21 insertions(+) > > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index 70314cd93340..31b9c06c9b3b 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -1601,6 +1601,21 @@ static void vmx_clear_hlt(struct kvm_vcpu *vcpu) > vmcs_write32(GUEST_ACTIVITY_STATE, GUEST_ACTIVITY_ACTIVE); > } > > +static void flip_arch_lbr_ctl(struct kvm_vcpu *vcpu, bool on) > +{ > + if (vcpu_to_pmu(vcpu)->event_count > 0 && Ugh, this check seems ridiculous/funny to me. > + kvm_cpu_cap_has(X86_FEATURE_ARCH_LBR)) { > + u64 lbr_ctl = vmcs_read64(GUEST_IA32_LBR_CTL); > + > + if (on) > + lbr_ctl |= 1ULL; > + else > + lbr_ctl &= ~1ULL; > + > + vmcs_write64(GUEST_IA32_LBR_CTL, lbr_ctl); > + } > +} ...