From nobody Fri Nov 7 09:11:03 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (209.51.188.17 [209.51.188.17]) by mx.zohomail.com with SMTPS id 1547477162394796.8544231551904; Mon, 14 Jan 2019 06:46:02 -0800 (PST) Received: from localhost ([127.0.0.1]:43502 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gj3Uy-0002g5-8G for importer@patchew.org; Mon, 14 Jan 2019 09:45:56 -0500 Received: from eggs.gnu.org ([209.51.188.92]:57020) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gj3KM-0000kd-Tx for qemu-devel@nongnu.org; Mon, 14 Jan 2019 09:34:59 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gj3KL-0005ki-19 for qemu-devel@nongnu.org; Mon, 14 Jan 2019 09:34:58 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55560) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gj3KK-0005kH-RS for qemu-devel@nongnu.org; Mon, 14 Jan 2019 09:34:56 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8CE79C0587CE; Mon, 14 Jan 2019 14:34:55 +0000 (UTC) Received: from localhost (ovpn-116-76.gru2.redhat.com [10.97.116.76]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1C9685D73F; Mon, 14 Jan 2019 14:34:51 +0000 (UTC) From: Eduardo Habkost To: Peter Maydell , qemu-devel@nongnu.org Date: Mon, 14 Jan 2019 12:34:32 -0200 Message-Id: <20190114143432.4771-6-ehabkost@redhat.com> In-Reply-To: <20190114143432.4771-1-ehabkost@redhat.com> References: <20190114143432.4771-1-ehabkost@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Mon, 14 Jan 2019 14:34:55 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 5/5] i386/kvm: add a comment explaining why .feat_names are commented out for Hyper-V feature bits X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , kvm@vger.kernel.org, "Michael S. Tsirkin" , Marcelo Tosatti , Paolo Bonzini , Vitaly Kuznetsov , Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: Vitaly Kuznetsov Hyper-V .feat_names are, unlike hardware features, commented out and it is not obvious why we do that. Document the current status quo. Signed-off-by: Vitaly Kuznetsov Message-Id: <20181221141604.16935-1-vkuznets@redhat.com> Signed-off-by: Eduardo Habkost --- target/i386/cpu.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 3ece83696e..2f5412592d 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -929,6 +929,13 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS= ] =3D { */ .no_autoenable_flags =3D ~0U, }, + /* + * .feat_names are commented out for Hyper-V enlightenments because we + * don't want to have two different ways for enabling them on QEMU com= mand + * line. Some features (e.g. "hyperv_time", "hyperv_vapic", ...) requi= re + * enabling several feature bits simultaneously, exposing these bits + * individually may just confuse guests. + */ [FEAT_HYPERV_EAX] =3D { .type =3D CPUID_FEATURE_WORD, .feat_names =3D { --=20 2.18.0.rc1.1.g3f1ff2140