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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D78CFC04A68 for ; Thu, 28 Jul 2022 22:25:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232769AbiG1WZY (ORCPT ); Thu, 28 Jul 2022 18:25:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232400AbiG1WZU (ORCPT ); Thu, 28 Jul 2022 18:25:20 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4F021A39C; Thu, 28 Jul 2022 15:25:19 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id i8so3935798wro.11; Thu, 28 Jul 2022 15:25:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=zhQMD8WNvOQjT/U1dXD2LRPZHwffkL9Bm1xxBkXDodc=; b=UR6fLSV9vHafCaddO1Qk21OI1NeVq6haLG9wZ0SD/mGCjSdUmOlvQQz5Tqis8R9IAL LxFqQEH6nKTGDHk9DT7mM7KvTA61mQ2BrECGwWZgnbSNA43v8m6AxKK1R2AfzPhbEwg6 hIK1Uh0OK5St9g1NqYpVoO4AApEDIYvsp0GvpC1fnbD2VLZhbdAeW7prfxPYwDVwMiFT W2ktKd1pksDRQmJfkeAH1fB4wzFfhGTa3cJ2uF8Vj8VqnTqQWoVGF8EqK3Dhn8pzapvR +ybMC/qI3j0cctXbsIajI5jAl5dArUaYnStdywKPJlJHJ1MXPNeDsCCJYtnb44tSoF+v y4/g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:message-id:date:mime-version:user-agent :subject:content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=zhQMD8WNvOQjT/U1dXD2LRPZHwffkL9Bm1xxBkXDodc=; b=nKjdAT0bzv3xR+6k4iuzR34IyKanSxEYufphOue+GQRaynMQp18B2b03WoPdYg6oPz St2skFNRvpCksOoufz4KprkInM6W/+eXMA++pz3RRgKTF2iSfph2MlNIUkYBKC5EEz8R FHGAuEYk7YLUK3UmAqndpeIVzKb/uI9mfsHdmC9+RdOWI4sgehsRvfoU32Ej5eFJOqQ7 +SP6/eJHN65dcc5NHfrzSOqOhALqjhXpHY7QWvRjhLnsRAvHMf/h3Gv0sPaERniPdB39 Cta8HzVWB3NmAdIRkgRFRYVRk1op/yvkP7CeZrlEFhV3E/YA1UQJcqEYlmXajQJpUdJ3 O7+A== X-Gm-Message-State: ACgBeo0XZ0hGzVzZ0NeIIt9d8eMgIcw8W8FQKrn9TJMFbQCSUzYDxlMz RER74V3mJX8VgSkGVOQAx9Y= X-Google-Smtp-Source: AA6agR5IDyzx1VeN0I77IjxK+eNJN7uyVZguAUOlCxa5sIyHOoL8qoXoewHvdsgsb7jgJXbMfIs7qQ== X-Received: by 2002:a5d:6b10:0:b0:21e:4bbd:e893 with SMTP id v16-20020a5d6b10000000b0021e4bbde893mr544856wrw.613.1659047118137; Thu, 28 Jul 2022 15:25:18 -0700 (PDT) Received: from ?IPV6:2001:b07:6468:f312:9af8:e5f5:7516:fa89? ([2001:b07:6468:f312:9af8:e5f5:7516:fa89]) by smtp.googlemail.com with ESMTPSA id s7-20020adfeb07000000b0021d6d9c0bd9sm1997314wrn.82.2022.07.28.15.25.17 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 28 Jul 2022 15:25:17 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <2e60bd73-e4da-eb4e-4eae-e43be7fd5bcd@redhat.com> Date: Fri, 29 Jul 2022 00:25:16 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH v4 21/25] KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config() Content-Language: en-US To: Sean Christopherson , Vitaly Kuznetsov Cc: kvm@vger.kernel.org, Anirudh Rayabharam , Wanpeng Li , Jim Mattson , Maxim Levitsky , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220714091327.1085353-1-vkuznets@redhat.com> <20220714091327.1085353-22-vkuznets@redhat.com> From: Paolo Bonzini In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/22/22 00:56, Sean Christopherson wrote: > Except the errata are based on FMS and the FMS exposed to the L1 hypervisor may > not be the real FMS. > > But that's moot, because they_should_ be fully emulated by KVM anyways; KVM > runs L2 with a MSR value modified by perf, not the raw MSR value requested by L1. > > Of course KVM screws things up and fails to clear the flag in entry controls... > All exit controls are emulated so at least KVM gets those right. Can you send this as a separate patch? Paolo > Untested, but I believe KVM the fix is: > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > index d0e781c7ac72..76926147b672 100644 > --- a/arch/x86/kvm/vmx/nested.c > +++ b/arch/x86/kvm/vmx/nested.c > @@ -2357,7 +2357,8 @@ static void prepare_vmcs02_early(struct vcpu_vmx *vmx, struct loaded_vmcs *vmcs0 > * we can avoid VMWrites during vmx_set_efer(). > */ > exec_control = __vm_entry_controls_get(vmcs01); > - exec_control |= vmcs12->vm_entry_controls; > + exec_control |= (vmcs12->vm_entry_controls & > + ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL); > exec_control &= ~(VM_ENTRY_IA32E_MODE | VM_ENTRY_LOAD_IA32_EFER); > if (cpu_has_load_ia32_efer()) { > if (guest_efer & EFER_LMA)