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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 70B11C43387 for ; Tue, 18 Dec 2018 08:16:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 42F1B214C6 for ; Tue, 18 Dec 2018 08:16:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726547AbeLRIQJ (ORCPT ); Tue, 18 Dec 2018 03:16:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45340 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726316AbeLRIQI (ORCPT ); Tue, 18 Dec 2018 03:16:08 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 56F1FC070E12; Tue, 18 Dec 2018 08:16:08 +0000 (UTC) Received: from vitty.brq.redhat.com.redhat.com (unknown [10.40.205.19]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AE8102C8FD; Tue, 18 Dec 2018 08:16:05 +0000 (UTC) From: Vitaly Kuznetsov To: Paolo Bonzini , kvm@vger.kernel.org Cc: Radim =?utf-8?B?S3LEjW3DocWZ?= , linux-kernel@vger.kernel.org, Roman Kagan , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , x86@kernel.org, "Michael Kelley \(EOSG\)" , Eduardo Habkost Subject: Re: [PATCH v2 0/7] x86/kvm/hyper-v: Implement KVM_GET_SUPPORTED_HV_CPUID In-Reply-To: References: <20181210172159.410-1-vkuznets@redhat.com> <7a318d1c-7601-fc67-8924-971f9deb8824@redhat.com> <87woo830o6.fsf@vitty.brq.redhat.com> Date: Tue, 18 Dec 2018 09:16:04 +0100 Message-ID: <87k1k72qt7.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 18 Dec 2018 08:16:08 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Paolo Bonzini writes: > On 17/12/18 11:30, Vitaly Kuznetsov wrote: >>> Queued, thanks. I moved this above the direct EOI series so that >>> KVM_CAP_HYPERV_STIMER_DIRECT need not exist at any point of the history. >>> >> Thanks! Just to make sure (and to conclude our discussion with Roman): >> with your Qemu maintainer hat on, do you agree with the design decision >> that KVM_GET_SUPPORTED_HV_CPUID's output value changes when >> KVM_CAP_HYPERV_ENLIGHTENED_VMCS gets enabled? This differs from >> KVM_GET_SUPPORTED_CPUID (where we always list all feature bits even if >> they require explicit enablement)? > > It doesn't really matter, since the old capability cannot be removed. > If you want to change it with a patch on top, that's also okay with me. Ok, let's leave it as it is: maybe some other userspace (which doesn't use legacy capabilities) will be grateful :-) -- Vitaly