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=-5.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,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 6AC00C388F7 for ; Thu, 22 Oct 2020 14:06:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 01A3D24182 for ; Thu, 22 Oct 2020 14:06:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="auu+H5J6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2900653AbgJVOGv (ORCPT ); Thu, 22 Oct 2020 10:06:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:48544 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2900642AbgJVOGv (ORCPT ); Thu, 22 Oct 2020 10:06:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603375609; 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=IksS0dWGNjACWPqrKqEiMIvP6KsFkhmhvk7S1rPtye8=; b=auu+H5J6yk2ytG6UydYefjj+onhnNSEYwgRvfSlaZtMyKArIqdHeelO8m7mjNRhGySIDxk H8LgXik/G/ZfdKdoNmRvMTTdIRbQiNJmxs80Ol0rNnAonMV6aRuUICLuH80rmDsBq+29+w tut6nIn1gOiaZdNp63zKm47OTU3bKiM= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-540-CBgnZqf3MO-ZeyN65TlyZA-1; Thu, 22 Oct 2020 10:06:48 -0400 X-MC-Unique: CBgnZqf3MO-ZeyN65TlyZA-1 Received: by mail-wr1-f70.google.com with SMTP id 47so663566wrc.19 for ; Thu, 22 Oct 2020 07:06:47 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:cc:references:from:subject:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=IksS0dWGNjACWPqrKqEiMIvP6KsFkhmhvk7S1rPtye8=; b=Z7gHiMb4eMNSMjLvBfIuetqLbk/YfI7BTY+YvTsf3BOPzlKPaFLuFzkzzUl2oKCPFJ JdI9j+7Zp+LJWfCv4k4dLUVdblwSA3AUiglPnioQ46RCvfiXf0jW2QHoISM6dH/jgj7A 5L7NqEoeDH+f06rLoRFxVLveZd4qXFabbIpx7vPeXE7R/7PcHeVvv2tFq/emVMRmkUJz xQhs3Ukk9mmPfo1LUHmerLvYmWPOzpgONgOrx6iegbS3OqHsjPThBFeIKFLT/sbf2hx3 MU90NJCEZTinvo0XAR9X8WSCslWaCT1Ik2k1yxw+Ab+BDs4dbq2gFV7YhOr7eWLSXGvt aeMg== X-Gm-Message-State: AOAM532EZwpmmun8gssosiQZ/Iu+uTkV74ZXeXjHB6JnrvRP3bXeHqGq FzbVLxuzLxif1Z62J7e3lOR1NVEdTH4nry7w4sNQexeWlulPCs/ihmJBhCrEg+IswhWpWGQva5Q 2x3vfUkaWZIkG5dly4qkAcJ1U X-Received: by 2002:a7b:c259:: with SMTP id b25mr2633247wmj.141.1603375606752; Thu, 22 Oct 2020 07:06:46 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzoNQeHJNOP1tlc5K9b2forzKL95uimESQ1LxcUbal3YLzrd4t5sn+mT1MWkl0piTT/MsTq0w== X-Received: by 2002:a7b:c259:: with SMTP id b25mr2633225wmj.141.1603375606556; Thu, 22 Oct 2020 07:06:46 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:c8dd:75d4:99ab:290a? ([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.gmail.com with ESMTPSA id 10sm4361466wmn.9.2020.10.22.07.06.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 22 Oct 2020 07:06:44 -0700 (PDT) To: Xiaoyao Li , Wanpeng Li , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel References: <1603330475-7063-1-git-send-email-wanpengli@tencent.com> <6ad94df6-9ecd-e364-296a-34ba41e938b1@intel.com> From: Paolo Bonzini Subject: Re: [PATCH] KVM: X86: Expose KVM_HINTS_REALTIME in KVM_GET_SUPPORTED_CPUID Message-ID: <31b189e0-503f-157d-7af0-329744ed5369@redhat.com> Date: Thu, 22 Oct 2020 16:06:43 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.1 MIME-Version: 1.0 In-Reply-To: <6ad94df6-9ecd-e364-296a-34ba41e938b1@intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22/10/20 15:31, Xiaoyao Li wrote: >> >> It's common for userspace to copy all supported CPUID bits to >> KVM_SET_CPUID2, I don't think this is the right behavior for >> KVM_HINTS_REALTIME. > > It reminds of X86_FEATURE_WAITPKG, which is added to supported CPUID > recently as a fix but QEMU exposes it to guest only when "-overcommit > cpu-pm" WAITPKG is not included in KVM_GET_SUPPORTED_CPUID either. QEMU detects it through the MSR_IA32_UMWAIT register. Paolo