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=-8.5 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,SIGNED_OFF_BY,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 5F258C388F9 for ; Thu, 22 Oct 2020 13:02:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 060962053B for ; Thu, 22 Oct 2020 13:02:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="MY87XrPH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2899211AbgJVNCZ (ORCPT ); Thu, 22 Oct 2020 09:02:25 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:41154 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2506747AbgJVNCZ (ORCPT ); Thu, 22 Oct 2020 09:02:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603371744; 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=+Baoti0rGPc8rx4Gu7rHbcn1CKN3zPD/a9Reidmnsr8=; b=MY87XrPHJxAeYzIgxFLgpjBbpa88WUH2Vr9H9c0QZtcvnhHVT2lVR+3VU7PNwLWgelMZEy E0k9IhfUQcTAb1twYqrYRm8FSwXwSCukF3gMsD/n1uTZC8DoNE17+GZysM6uUUOQ3WjYdT b/8J2tVKYvE+q4IT6rBjzpfv4Ue1LFw= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-487-Xjm4QLyAOUG7sYm-FLdnVQ-1; Thu, 22 Oct 2020 09:02:22 -0400 X-MC-Unique: Xjm4QLyAOUG7sYm-FLdnVQ-1 Received: by mail-wr1-f69.google.com with SMTP id n14so603919wrp.1 for ; Thu, 22 Oct 2020 06:02:22 -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=+Baoti0rGPc8rx4Gu7rHbcn1CKN3zPD/a9Reidmnsr8=; b=FIC7oevZCtdLEuPRUUP/PAUsr50cyzQADiyIj1/MVlaKgh9R9jstGTAiGiwOynLajh GW9FQ+XZjHCI2u0GCe05p7tbqs8IjAMC41A0SMEkL5YPUKX4sL8jE9vNYNadGuorpLLj xxIYoZXgEp6rr+N7X+FFwvtgAAF50PX7UpMtrPSw+usyO8ks2wmI6cQ9tAWQuVpN0uGd 2I7K8PVfTtw04/+77rrYDpd5dY7uh6WFdtslRlFr3vsWIOhi6XIiDsoj3KGlMlzZ1ZzM X8OONNTuJg3HqfvhnRZov+MqI1NhBMqQBnVVfLuIn4CRPifBsXnKYax5j6oO1BJQdgmT HNRg== X-Gm-Message-State: AOAM531TpdXduZzqciASws2Hxk3W420s4j4VucwzZ8xOJpzx1bCspDam lTN2Fdr52CSIJ6nFTTUZuaz6VacQV44mNx00hhe4HiueBOxbX/AlTkWHAcGS/oXW3OrX+/38Fd7 9qMs6P9++de4uZaLqlqNWnme4 X-Received: by 2002:adf:97cb:: with SMTP id t11mr2834620wrb.292.1603371741247; Thu, 22 Oct 2020 06:02:21 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwdR80pHuceIpF8ybnwX11kJxDdRfn6kU7dlv3coiblTzqqD1XBYYiyCglWKy6psAXPxI56Vw== X-Received: by 2002:adf:97cb:: with SMTP id t11mr2834592wrb.292.1603371741051; Thu, 22 Oct 2020 06:02:21 -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 l1sm4022890wrb.1.2020.10.22.06.02.17 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 22 Oct 2020 06:02:18 -0700 (PDT) Subject: Re: [PATCH] KVM: X86: Expose KVM_HINTS_REALTIME in KVM_GET_SUPPORTED_CPUID To: 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> From: Paolo Bonzini Message-ID: Date: Thu, 22 Oct 2020 15:02:17 +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: <1603330475-7063-1-git-send-email-wanpengli@tencent.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22/10/20 03:34, Wanpeng Li wrote: > From: Wanpeng Li > > Per KVM_GET_SUPPORTED_CPUID ioctl documentation: > > This ioctl returns x86 cpuid features which are supported by both the > hardware and kvm in its default configuration. > > A well-behaved userspace should not set the bit if it is not supported. > > Suggested-by: Jim Mattson > Signed-off-by: Wanpeng Li 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. (But maybe this was discussed already; if so, please point me to the previous discussion). Paolo