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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_NEOMUTT 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 53864C48BD7 for ; Thu, 27 Jun 2019 11:58:06 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2C47F20656 for ; Thu, 27 Jun 2019 11:58:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C47F20656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49214 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hgT2T-0003im-Fy for qemu-devel@archiver.kernel.org; Thu, 27 Jun 2019 07:58:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39336) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hgT0o-0001e5-Eo for qemu-devel@nongnu.org; Thu, 27 Jun 2019 07:56:23 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hgT0m-0004No-Tl for qemu-devel@nongnu.org; Thu, 27 Jun 2019 07:56:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44216) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hgT0j-0004I5-9L; Thu, 27 Jun 2019 07:56:17 -0400 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 79C4B3082E63; Thu, 27 Jun 2019 11:56:11 +0000 (UTC) Received: from kamzik.brq.redhat.com (unknown [10.43.2.160]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A4E54614D8; Thu, 27 Jun 2019 11:56:08 +0000 (UTC) Date: Thu, 27 Jun 2019 13:56:06 +0200 From: Andrew Jones To: Richard Henderson Message-ID: <20190627115606.c3pd3acjhufntrvr@kamzik.brq.redhat.com> References: <20190621163422.6127-1-drjones@redhat.com> <20190621163422.6127-12-drjones@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 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 [10.5.110.46]); Thu, 27 Jun 2019 11:56:15 +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: Re: [Qemu-devel] [PATCH v2 11/14] target/arm/kvm64: max cpu: Enable SVE when available X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org, qemu-devel@nongnu.org, armbru@redhat.com, eric.auger@redhat.com, qemu-arm@nongnu.org, imammedo@redhat.com, alex.bennee@linaro.org, Dave.Martin@arm.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Jun 26, 2019 at 01:09:45PM +0200, Richard Henderson wrote: > On 6/21/19 6:34 PM, Andrew Jones wrote: > > @@ -675,6 +689,11 @@ static void aarch64_max_initfn(Object *obj) > > > > if (kvm_enabled()) { > > kvm_arm_set_cpu_features_from_host(cpu); > > + /* > > + * KVM doesn't yet support the sve-max-vq property, but > > + * setting cpu->sve_max_vq is also used to turn SVE on. > > + */ > > + cpu->sve_max_vq = ARM_SVE_INIT; > > Can we support this value with KVM_GET/SET_ONE_REG on ZCR_EL2? (IIRC KVM > requires VHE to support SVE, so the host is always EL2 and the guest is always > EL1.) > > Or do we need to probe this via normal userland prctl? > > Or am I getting ahead of the patches to follow? Hopefully mostly this, because I didn't understand the concern with VHE. If it still looks like something is missing after looking at other patches, then please come back to this to help me understand. Thanks, drew