From nobody Sat May 4 08:37:54 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.zoho.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; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1494328967597659.1610178999667; Tue, 9 May 2017 04:22:47 -0700 (PDT) Received: from localhost ([::1]:36501 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d83E5-0006A2-Aw for importer@patchew.org; Tue, 09 May 2017 07:22:45 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56674) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d83C8-0004jn-9s for qemu-devel@nongnu.org; Tue, 09 May 2017 07:20:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d83C7-00058s-25 for qemu-devel@nongnu.org; Tue, 09 May 2017 07:20:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57392) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d83C6-00058j-Ro for qemu-devel@nongnu.org; Tue, 09 May 2017 07:20:42 -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 CF450461EA; Tue, 9 May 2017 11:20:41 +0000 (UTC) Received: from t460.redhat.com (ovpn-117-114.ams2.redhat.com [10.36.117.114]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9907C7839D; Tue, 9 May 2017 11:20:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com CF450461EA Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=berrange@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com CF450461EA From: "Daniel P. Berrange" To: qemu-devel@nongnu.org Date: Tue, 9 May 2017 12:20:33 +0100 Message-Id: <20170509112034.23351-2-berrange@redhat.com> In-Reply-To: <20170509112034.23351-1-berrange@redhat.com> References: <20170509112034.23351-1-berrange@redhat.com> 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 [10.5.110.29]); Tue, 09 May 2017 11:20:42 +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] [PATCH v3 1/2] i386: rewrite way CPUID index is validated 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 , 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" Change the nested if statements into a flat format, to make it clearer what validation / capping is being performed on different CPUID index values. Signed-off-by: Daniel P. Berrange Reviewed-by: Eduardo Habkost --- target/i386/cpu.c | 35 +++++++++++++++-------------------- 1 file changed, 15 insertions(+), 20 deletions(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 13c0985..8cb4af4 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -2626,28 +2626,23 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index= , uint32_t count, X86CPU *cpu =3D x86_env_get_cpu(env); CPUState *cs =3D CPU(cpu); uint32_t pkg_offset; + uint32_t limit; =20 - /* test if maximum index reached */ - if (index & 0x80000000) { - if (index > env->cpuid_xlevel) { - if (env->cpuid_xlevel2 > 0) { - /* Handle the Centaur's CPUID instruction. */ - if (index > env->cpuid_xlevel2) { - index =3D env->cpuid_xlevel2; - } else if (index < 0xC0000000) { - index =3D env->cpuid_xlevel; - } - } else { - /* Intel documentation states that invalid EAX input will - * return the same information as EAX=3Dcpuid_level - * (Intel SDM Vol. 2A - Instruction Set Reference - CPUID) - */ - index =3D env->cpuid_level; - } - } + /* Calculate & apply limits for different index ranges */ + if (index >=3D 0xC0000000) { + limit =3D env->cpuid_xlevel2; + } else if (index >=3D 0x80000000) { + limit =3D env->cpuid_xlevel; } else { - if (index > env->cpuid_level) - index =3D env->cpuid_level; + limit =3D env->cpuid_level; + } + + if (index > limit) { + /* Intel documentation states that invalid EAX input will + * return the same information as EAX=3Dcpuid_level + * (Intel SDM Vol. 2A - Instruction Set Reference - CPUID) + */ + index =3D env->cpuid_level; } =20 switch(index) { --=20 2.9.3 From nobody Sat May 4 08:37:54 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.zoho.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; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1494328945764914.9647789081768; Tue, 9 May 2017 04:22:25 -0700 (PDT) Received: from localhost ([::1]:36500 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d83Dh-0005cc-AY for importer@patchew.org; Tue, 09 May 2017 07:22:21 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56703) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d83CA-0004lh-Mf for qemu-devel@nongnu.org; Tue, 09 May 2017 07:20:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d83C9-00059n-O3 for qemu-devel@nongnu.org; Tue, 09 May 2017 07:20:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56662) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d83C9-00059S-Et for qemu-devel@nongnu.org; Tue, 09 May 2017 07:20:45 -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 71EB04DD5F; Tue, 9 May 2017 11:20:44 +0000 (UTC) Received: from t460.redhat.com (ovpn-117-114.ams2.redhat.com [10.36.117.114]) by smtp.corp.redhat.com (Postfix) with ESMTP id 68D1A78398; Tue, 9 May 2017 11:20:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 71EB04DD5F Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=berrange@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 71EB04DD5F From: "Daniel P. Berrange" To: qemu-devel@nongnu.org Date: Tue, 9 May 2017 12:20:34 +0100 Message-Id: <20170509112034.23351-3-berrange@redhat.com> In-Reply-To: <20170509112034.23351-1-berrange@redhat.com> References: <20170509112034.23351-1-berrange@redhat.com> 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 [10.5.110.38]); Tue, 09 May 2017 11:20:44 +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] [PATCH v3 2/2] i386: expose "TCGTCGTCGTCG" in the 0x40000000 CPUID leaf 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 , 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" Currently when running KVM, we expose "KVMKVMKVM\0\0\0" in the 0x40000000 CPUID leaf. Other hypervisors (VMWare, HyperV, Xen, BHyve) all do the same thing, which leaves TCG as the odd one out. The CPUID signature is used by software to detect which virtual environment they are running in and (potentially) change behaviour in certain ways. For example, systemd supports a ConditionVirtualization=3D setting in unit files. The virt-what command can also report the virt type it is running on Currently both these apps have to resort to custom hacks like looking for 'fw-cfg' entry in the /proc/device-tree file to identify TCG. This change thus proposes a signature "TCGTCGTCGTCG" to be reported when running under TCG. To hide this, the -cpu option tcg-cpuid=3Doff can be used. Signed-off-by: Daniel P. Berrange --- include/hw/i386/pc.h | 5 +++++ target/i386/cpu.c | 22 ++++++++++++++++++++++ target/i386/cpu.h | 1 + 3 files changed, 28 insertions(+) diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h index f278b3a..3aec60f 100644 --- a/include/hw/i386/pc.h +++ b/include/hw/i386/pc.h @@ -376,6 +376,11 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_= t *); #define PC_COMPAT_2_8 \ HW_COMPAT_2_8 \ {\ + .driver =3D TYPE_X86_CPU,\ + .property =3D "tcg-cpuid",\ + .value =3D "off",\ + },\ + {\ .driver =3D "kvmclock",\ .property =3D "x-mach-use-reliable-get-clock",\ .value =3D "off",\ diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 8cb4af4..ee4f515 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -2627,12 +2627,15 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index= , uint32_t count, CPUState *cs =3D CPU(cpu); uint32_t pkg_offset; uint32_t limit; + uint32_t signature[3]; =20 /* Calculate & apply limits for different index ranges */ if (index >=3D 0xC0000000) { limit =3D env->cpuid_xlevel2; } else if (index >=3D 0x80000000) { limit =3D env->cpuid_xlevel; + } else if (index & 0x40000000) { + limit =3D 0x40000000; } else { limit =3D env->cpuid_level; } @@ -2867,6 +2870,24 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,= uint32_t count, } break; } + case 0x40000000: + /* + * CPUID code in kvm_arch_init_vcpu() ignores stuff + * set here, but we restrict to TCG none the less. + */ + if (tcg_enabled() && cpu->expose_tcg) { + memcpy(signature, "TCGTCGTCGTCG", 12); + *eax =3D 0; + *ebx =3D signature[0]; + *ecx =3D signature[1]; + *edx =3D signature[2]; + } else { + *eax =3D 0; + *ebx =3D 0; + *ecx =3D 0; + *edx =3D 0; + } + break; case 0x80000000: *eax =3D env->cpuid_xlevel; *ebx =3D env->cpuid_vendor1; @@ -4008,6 +4029,7 @@ static Property x86_cpu_properties[] =3D { DEFINE_PROP_BOOL("kvm-no-smi-migration", X86CPU, kvm_no_smi_migration, false), DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true), + DEFINE_PROP_BOOL("tcg-cpuid", X86CPU, expose_tcg, true), DEFINE_PROP_END_OF_LIST() }; =20 diff --git a/target/i386/cpu.h b/target/i386/cpu.h index c4602ca..c25f0ce 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -1216,6 +1216,7 @@ struct X86CPU { bool check_cpuid; bool enforce_cpuid; bool expose_kvm; + bool expose_tcg; bool migratable; bool max_features; /* Enable all supported features automatically */ uint32_t apic_id; --=20 2.9.3