From nobody Sun May 5 16:59:07 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 1494336611506592.5904292474721; Tue, 9 May 2017 06:30:11 -0700 (PDT) Received: from localhost ([::1]:37300 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d85DM-0004LO-2k for importer@patchew.org; Tue, 09 May 2017 09:30:08 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58218) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d85B6-0002hF-9b for qemu-devel@nongnu.org; Tue, 09 May 2017 09:27:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d85B3-00084J-Ai for qemu-devel@nongnu.org; Tue, 09 May 2017 09:27:48 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40350) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d85B3-00083H-3e for qemu-devel@nongnu.org; Tue, 09 May 2017 09:27:45 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1404064F6; Tue, 9 May 2017 13:27:44 +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 194097E915; Tue, 9 May 2017 13:27:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 1404064F6 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 1404064F6 From: "Daniel P. Berrange" To: qemu-devel@nongnu.org Date: Tue, 9 May 2017 14:27:35 +0100 Message-Id: <20170509132736.10071-2-berrange@redhat.com> In-Reply-To: <20170509132736.10071-1-berrange@redhat.com> References: <20170509132736.10071-1-berrange@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 09 May 2017 13:27:44 +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 v4 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. NB this changes behaviour when "index > env->cpuid_xlevel2". This won't have any guest-visible effect because no there is no CPUID[0xC0000001] feature supported by TCG, and KVM code will never call cpu_x86_cpuid() with such an index value. Reviewed-by: Eduardo Habkost Signed-off-by: Daniel P. Berrange --- 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 Sun May 5 16:59:07 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 1494336538945986.0637732742074; Tue, 9 May 2017 06:28:58 -0700 (PDT) Received: from localhost ([::1]:37287 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d85CD-0003Nm-JD for importer@patchew.org; Tue, 09 May 2017 09:28:57 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58220) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d85B6-0002hH-9z for qemu-devel@nongnu.org; Tue, 09 May 2017 09:27:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d85B4-000863-SS for qemu-devel@nongnu.org; Tue, 09 May 2017 09:27:48 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50292) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d85B4-00085C-Iy for qemu-devel@nongnu.org; Tue, 09 May 2017 09:27:46 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8CC40C04B93B; Tue, 9 May 2017 13:27:45 +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 57DF07E915; Tue, 9 May 2017 13:27:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 8CC40C04B93B Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=berrange@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 8CC40C04B93B From: "Daniel P. Berrange" To: qemu-devel@nongnu.org Date: Tue, 9 May 2017 14:27:36 +0100 Message-Id: <20170509132736.10071-3-berrange@redhat.com> In-Reply-To: <20170509132736.10071-1-berrange@redhat.com> References: <20170509132736.10071-1-berrange@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 09 May 2017 13:27:45 +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 v4 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 | 28 ++++++++++++++++++++++++++++ target/i386/cpu.h | 1 + 3 files changed, 34 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..edf451c 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 >=3D 0x40000000) { + limit =3D 0x40000001; } else { limit =3D env->cpuid_level; } @@ -2867,6 +2870,30 @@ 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 0x40000001; + *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 0x40000001: + *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 +4035,7 @@ 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