From nobody Thu Apr 25 17:11:13 2024 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 1523897031426776.3097116929306; Mon, 16 Apr 2018 09:43:51 -0700 (PDT) Received: from localhost ([::1]:57305 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f87EG-00048g-Gb for importer@patchew.org; Mon, 16 Apr 2018 12:43:44 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47648) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f87Ag-0001fW-4c for qemu-devel@nongnu.org; Mon, 16 Apr 2018 12:40:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f87Af-0006qf-4W for qemu-devel@nongnu.org; Mon, 16 Apr 2018 12:40:02 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41748) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f87Ae-0006qG-Up for qemu-devel@nongnu.org; Mon, 16 Apr 2018 12:40:01 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 339BD80F93; Mon, 16 Apr 2018 16:40:00 +0000 (UTC) Received: from localhost (ovpn-116-12.gru2.redhat.com [10.97.116.12]) by smtp.corp.redhat.com (Postfix) with ESMTP id 34FF57E4F5; Mon, 16 Apr 2018 16:39:57 +0000 (UTC) From: Eduardo Habkost To: Peter Maydell Date: Mon, 16 Apr 2018 13:39:53 -0300 Message-Id: <20180416163953.31188-2-ehabkost@redhat.com> In-Reply-To: <20180416163953.31188-1-ehabkost@redhat.com> References: <20180416163953.31188-1-ehabkost@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 16 Apr 2018 16:40:00 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 1/1] i386: Don't automatically enable FEAT_KVM_HINTS 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: Paolo Bonzini , qemu-devel@nongnu.org, 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" The assumption in the cpu->max_features code is that anything enabled on GET_SUPPORTED_CPUID should be enabled on "-cpu host". This shouldn't be the case for FEAT_KVM_HINTS. This adds a new FeatureWordInfo::no_autoenable_flags field, that can be used to prevent FEAT_KVM_HINTS bits to be enabled automatically. Reviewed-by: Paolo Bonzini Signed-off-by: Eduardo Habkost Message-Id: <20180410211534.26079-1-ehabkost@redhat.com> Tested-by: Wanpeng Li Signed-off-by: Eduardo Habkost --- target/i386/cpu.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 1a6b082b6f..a20fe26573 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -295,6 +295,8 @@ typedef struct FeatureWordInfo { uint32_t tcg_features; /* Feature flags supported by TCG */ uint32_t unmigratable_flags; /* Feature flags known to be unmigratable= */ uint32_t migratable_flags; /* Feature flags known to be migratable */ + /* Features that shouldn't be auto-enabled by "-cpu host" */ + uint32_t no_autoenable_flags; } FeatureWordInfo; =20 static FeatureWordInfo feature_word_info[FEATURE_WORDS] =3D { @@ -400,6 +402,11 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS= ] =3D { }, .cpuid_eax =3D KVM_CPUID_FEATURES, .cpuid_reg =3D R_EDX, .tcg_features =3D TCG_KVM_FEATURES, + /* + * KVM hints aren't auto-enabled by -cpu host, they need to be + * explicitly enabled in the command-line. + */ + .no_autoenable_flags =3D ~0U, }, [FEAT_HYPERV_EAX] =3D { .feat_names =3D { @@ -4062,7 +4069,8 @@ static void x86_cpu_expand_features(X86CPU *cpu, Erro= r **errp) */ env->features[w] |=3D x86_cpu_get_supported_feature_word(w, cpu->migratable) & - ~env->user_features[w]; + ~env->user_features[w] & \ + ~feature_word_info[w].no_autoenable_flags; } } =20 --=20 2.14.3