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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 4BF55C433E1 for ; Thu, 21 May 2020 08:24:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2B4CD2070A for ; Thu, 21 May 2020 08:24:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="KiS63N3C" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728590AbgEUIY2 (ORCPT ); Thu, 21 May 2020 04:24:28 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:29559 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728374AbgEUIY2 (ORCPT ); Thu, 21 May 2020 04:24:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590049467; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UgPlPKwQ78SmEvwlM+tSnD4eOCAOdkr7Ntl2fCb3Qdo=; b=KiS63N3Cn7Czi5DVNZGyjNaxec7dLbyPv4piB4gVvc776I0UdY/hFDUKDkwLBrApkfuT/U 3FB8opFdS3gpc9WHzuLuJqx+ltoawgPsWDMFqvEQc0uWHdRK70kjlzGu8njB9Rfu59nSYt ggQAeYpz9afFTmSC+O3b2rdqJjCxkzo= Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-167-HFw0fZHhMRSxz11tr1JoSA-1; Thu, 21 May 2020 04:24:25 -0400 X-MC-Unique: HFw0fZHhMRSxz11tr1JoSA-1 Received: by mail-ed1-f70.google.com with SMTP id a18so2509819eds.9 for ; Thu, 21 May 2020 01:24:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=UgPlPKwQ78SmEvwlM+tSnD4eOCAOdkr7Ntl2fCb3Qdo=; b=rBAvkKt+RFxH8/MxsuJUZf8Rm4mO5XkzTOOVfeCng32vC5SxKI+LUw7DK/Yw6VJBMc SmyxjLFmgwoAFTD7ztBRcQaBgtKRc5S3Vkwce2B/6Tx1D3+xhbqYqRCwPKZjHqmqoU9q vSV1eJRzKy7+fOPHvVfWpty0DyTEXcx5DHRgyfAiPHcRxfJrah1Ssg/bAi5RElRE2CID O+doqONUFYuv+aZ3qGI0zs8owX1jou65ahbs9TqwgkCrCT6P1s9vySHF1IwWVSB+yCzY Kt8qRvbWuKrRE8/Fc5ybKz5vjAkQJjd1O7WfA1b3Fl3uzx8w5au+su82MXKYJYj8QnC9 TtQQ== X-Gm-Message-State: AOAM530FeFDuTQwmRQNQ2reC8OxcdkJ5jhehsNXxYVTEHRlGmXcgnS03 bYaXgHLE+QVixBnyVOQQiFaeifyoVaF5o358eGRfRVn5jVAbqpOU5TjOdyAEhBkCyigzjGZXvWh 9JG1JY0H9GGlzIjqXXbNL3OQw X-Received: by 2002:a17:907:9d5:: with SMTP id bx21mr2366556ejc.510.1590049464362; Thu, 21 May 2020 01:24:24 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyoFKBT/y+lQ+LBEKa1W8bfwlzO4IvlNszMAjhIGGbGZEJr2l2PRpnaSFM+8x03wohqDEKpng== X-Received: by 2002:a17:907:9d5:: with SMTP id bx21mr2366545ejc.510.1590049464136; Thu, 21 May 2020 01:24:24 -0700 (PDT) Received: from [192.168.178.58] ([151.30.94.134]) by smtp.gmail.com with ESMTPSA id s20sm4204784eju.96.2020.05.21.01.24.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 May 2020 01:24:23 -0700 (PDT) Subject: Re: [PATCH 2/2] kvm/x86: don't expose MSR_IA32_UMWAIT_CONTROL unconditionally To: Xiaoyao Li , Maxim Levitsky , kvm@vger.kernel.org, Tao Xu Cc: linux-kernel@vger.kernel.org References: <20200520160740.6144-1-mlevitsk@redhat.com> <20200520160740.6144-3-mlevitsk@redhat.com> <81228a0e-7797-4f34-3d6d-5b0550c10a8f@intel.com> From: Paolo Bonzini Message-ID: <13f16f34-ce01-4207-1d1d-775b15a1e0f7@redhat.com> Date: Thu, 21 May 2020 10:24:22 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <81228a0e-7797-4f34-3d6d-5b0550c10a8f@intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/05/20 06:33, Xiaoyao Li wrote: > I remember there is certainly some reason why we don't expose WAITPKG to > guest by default. That's a userspace policy decision. KVM_GET_SUPPORTED_CPUID should still tell userspace that it's supported. Paolo > Tao, please help clarify it.