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=-12.8 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,SPF_HELO_NONE,SPF_PASS 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 B3B03C2B9F4 for ; Thu, 17 Jun 2021 04:33:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79882613BF for ; Thu, 17 Jun 2021 04:33:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229677AbhFQEfa (ORCPT ); Thu, 17 Jun 2021 00:35:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229515AbhFQEf3 (ORCPT ); Thu, 17 Jun 2021 00:35:29 -0400 Received: from mail-oi1-x22f.google.com (mail-oi1-x22f.google.com [IPv6:2607:f8b0:4864:20::22f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9068CC061574; Wed, 16 Jun 2021 21:33:22 -0700 (PDT) Received: by mail-oi1-x22f.google.com with SMTP id s23so5052631oiw.9; Wed, 16 Jun 2021 21:33:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=l93nAEQWQVGgYjPJ36XXH2GA9smqr9t+XyPLE0ZcqFU=; b=WM4BIBJYAR9/GNqzGaAm7/afPEFOtfLVJylAR7UtTxDF4EtLlXlxo2FlUkpt3eunCR kGlDhLJM2qDcy8mqvlWWmuqgPFBeT3nTZwv55IA1Qw4G1KvMg6iZvBa9yL2yr/d0lUpQ UD0Qt/0MNDJqrBKIDVG22MJaOH5WedGeDRqPDsV030xoAUugJzeQ28Bi3dxUOfdfNE/8 n3hVYR20/20IVFUBI0HYKWpxXTNtXSNKX0gZ9vmU25Wva2QlYFiVRlGrieUNMcYGNJSv xknDT9lUjdBPJVO3tc3ZYk3KbdrHWUNP+t8MXQ2AN2MmOTI67G+Ffqx0pLo1hrFi8J07 tIww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=l93nAEQWQVGgYjPJ36XXH2GA9smqr9t+XyPLE0ZcqFU=; b=VDuvfgylk5NfYC3WmRa3chirge6iNIuwKISNSOOZtfjCv4xfxAQ8soK5S7OLcKvCAs xFP9WVTXo/Mo6F/IJP3cu71Xh1rggYcZ1yDK+x7UjevxDv3GOSwqIXHNfNKmzBDES5Ls hrdMP3iZ/dyum80bIYmngVzzKkuY083sMQjZSNLL2jscPcUzDFg0kvCmOhlq9CpAa5eA k9IEP8LraZCNHlHYaWjXlZjRFHhDYxeOqnfKyYzC8yHSxbPrNrWMxEEN3qKKevi2uqGf YwtxsTOWdQsZTalbF/n5XgjBtNaJQnM9sr3FOL3B8smtTw1MNwtGsKMKbxIpEbpVhClR QWWg== X-Gm-Message-State: AOAM5309zneZPt3ezZv0t8AfLsZnvxonnLYhW2vFJAuyI3E6C4KP1mvU 7E8Y0RJal/5b7fqYJWQ3FhtaTMuddptCRvSxWCcBN9wS X-Google-Smtp-Source: ABdhPJxz5W3otMY5FhU2TFi+zV2IjT4OV7DdapjsYvWvoLcbPMOsT0TtS8dft+AwmFb/YRe9EzwK3aHQpnxNOgDAzlY= X-Received: by 2002:aca:b609:: with SMTP id g9mr9310954oif.141.1623904401734; Wed, 16 Jun 2021 21:33:21 -0700 (PDT) MIME-Version: 1.0 References: <1623223000-18116-1-git-send-email-wanpengli@tencent.com> In-Reply-To: <1623223000-18116-1-git-send-email-wanpengli@tencent.com> From: Wanpeng Li Date: Thu, 17 Jun 2021 12:33:09 +0800 Message-ID: Subject: Re: [PATCH v3] KVM: LAPIC: Keep stored TMCCT register value 0 after KVM_SET_LAPIC To: LKML , kvm Cc: Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org kindly ping, :) On Wed, 9 Jun 2021 at 15:17, Wanpeng Li wrote: > > From: Wanpeng Li > > KVM_GET_LAPIC stores the current value of TMCCT and KVM_SET_LAPIC's memcpy > stores it in vcpu->arch.apic->regs, KVM_SET_LAPIC could store zero in > vcpu->arch.apic->regs after it uses it, and then the stored value would > always be zero. In addition, the TMCCT is always computed on-demand and > never directly readable. > > Suggested-by: Paolo Bonzini > Signed-off-by: Wanpeng Li > --- > arch/x86/kvm/lapic.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 6d72d8f43310..9bd29b3ca790 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -2628,6 +2628,7 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) > apic_manage_nmi_watchdog(apic, kvm_lapic_get_reg(apic, APIC_LVT0)); > update_divide_count(apic); > __start_apic_timer(apic, APIC_TMCCT); > + kvm_lapic_set_reg(apic, APIC_TMCCT, 0); > kvm_apic_update_apicv(vcpu); > apic->highest_isr_cache = -1; > if (vcpu->arch.apicv_active) { > -- > 2.25.1 >