From nobody Sat Oct 25 21:46:09 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; 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 208.118.235.17 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 (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1521219749472446.88693892233925; Fri, 16 Mar 2018 10:02:29 -0700 (PDT) Received: from localhost ([::1]:58589 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ewskO-0006bo-N0 for importer@patchew.org; Fri, 16 Mar 2018 13:02:28 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57117) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ewsid-0005dS-0t for qemu-devel@nongnu.org; Fri, 16 Mar 2018 13:00:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ewsiX-0005Xc-J0 for qemu-devel@nongnu.org; Fri, 16 Mar 2018 13:00:39 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:55936 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ewsiX-0005X9-Fg for qemu-devel@nongnu.org; Fri, 16 Mar 2018 13:00:33 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 582B7D1449; Fri, 16 Mar 2018 17:00:29 +0000 (UTC) Received: from vitty.brq.redhat.com (unknown [10.43.2.155]) by smtp.corp.redhat.com (Postfix) with ESMTP id 443C62029296; Fri, 16 Mar 2018 17:00:28 +0000 (UTC) From: Vitaly Kuznetsov To: Paolo Bonzini Date: Fri, 16 Mar 2018 18:00:20 +0100 Message-Id: <20180316170020.8212-3-vkuznets@redhat.com> In-Reply-To: <20180316170020.8212-1-vkuznets@redhat.com> References: <20180316170020.8212-1-vkuznets@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Fri, 16 Mar 2018 17:00:29 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Fri, 16 Mar 2018 17:00:29 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'vkuznets@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v2 2/2] i386/kvm: lower requirements for Hyper-V frequency MSRs exposure 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: qemu-devel@nongnu.org, Roman Kagan , Marcelo Tosatti , Eduardo Habkost , Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Requiring tsc_is_stable_and_known() is too restrictive: even without INVTCS nested Hyper-V-on-KVM enables TSC pages for its guests e.g. when Reenlightenment MSRs are present. Presence of frequency MSRs doesn't mean these frequencies are stable, it just means they're available for reading. Signed-off-by: Vitaly Kuznetsov --- target/i386/kvm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/target/i386/kvm.c b/target/i386/kvm.c index accf50eac3..a6d1210f46 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -650,7 +650,7 @@ static int hyperv_handle_properties(CPUState *cs) env->features[FEAT_HYPERV_EAX] |=3D HV_TIME_REF_COUNT_AVAILABLE; env->features[FEAT_HYPERV_EAX] |=3D HV_REFERENCE_TSC_AVAILABLE; =20 - if (has_msr_hv_frequencies && tsc_is_stable_and_known(env)) { + if (has_msr_hv_frequencies && env->tsc_khz) { env->features[FEAT_HYPERV_EAX] |=3D HV_ACCESS_FREQUENCY_MSRS; env->features[FEAT_HYPERV_EDX] |=3D HV_FREQUENCY_MSRS_AVAILABL= E; } --=20 2.14.3