From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [RFC PATCH] kvm: Enable -cpu option to hide KVM Date: Sun, 01 Jun 2014 20:29:19 +0200 Message-ID: <538B70FF.6050103@redhat.com> References: <20140601162414.28708.22775.stgit@bling.home> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Alex Williamson , qemu-devel@nongnu.org Return-path: Received: from mail-we0-f173.google.com ([74.125.82.173]:45302 "EHLO mail-we0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750965AbaFAS3Y (ORCPT ); Sun, 1 Jun 2014 14:29:24 -0400 Received: by mail-we0-f173.google.com with SMTP id u57so4157396wes.4 for ; Sun, 01 Jun 2014 11:29:22 -0700 (PDT) In-Reply-To: <20140601162414.28708.22775.stgit@bling.home> Sender: kvm-owner@vger.kernel.org List-ID: Il 01/06/2014 18:25, Alex Williamson ha scritto: > The latest Nvidia driver (337.88) specifically checks for KVM as the > hypervisor and reports Code 43 for the driver in a Windows guest when > found. Removing or changing the KVM signature is sufficient to allow > the driver to load. This patch adds an option to easily allow the KVM > hypervisor signature to be hidden using '-cpu no-kvm'. > > Signed-off-by: Alex Williamson It's really a nit, but I think "kvm=no" is preferrable (more consistent with how hyper-v leaves are enabled). Paolo > --- > target-i386/cpu-qom.h | 1 + > target-i386/cpu.c | 1 + > target-i386/kvm.c | 28 +++++++++++++++------------- > 3 files changed, 17 insertions(+), 13 deletions(-) > > diff --git a/target-i386/cpu-qom.h b/target-i386/cpu-qom.h > index e9b3d57..99bb059 100644 > --- a/target-i386/cpu-qom.h > +++ b/target-i386/cpu-qom.h > @@ -87,6 +87,7 @@ typedef struct X86CPU { > bool hyperv_time; > bool check_cpuid; > bool enforce_cpuid; > + bool no_kvm; > > /* if true the CPUID code directly forward host cache leaves to the guest */ > bool cache_info_passthrough; > diff --git a/target-i386/cpu.c b/target-i386/cpu.c > index 042a48d..8e6ce9c 100644 > --- a/target-i386/cpu.c > +++ b/target-i386/cpu.c > @@ -2792,6 +2792,7 @@ static Property x86_cpu_properties[] = { > DEFINE_PROP_BOOL("hv-time", X86CPU, hyperv_time, false), > DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, false), > DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false), > + DEFINE_PROP_BOOL("no-kvm", X86CPU, no_kvm, false), > DEFINE_PROP_END_OF_LIST() > }; > > diff --git a/target-i386/kvm.c b/target-i386/kvm.c > index 0d894ef..920898e 100644 > --- a/target-i386/kvm.c > +++ b/target-i386/kvm.c > @@ -528,23 +528,25 @@ int kvm_arch_init_vcpu(CPUState *cs) > has_msr_hv_hypercall = true; > } > > - memcpy(signature, "KVMKVMKVM\0\0\0", 12); > - c = &cpuid_data.entries[cpuid_i++]; > - c->function = KVM_CPUID_SIGNATURE | kvm_base; > - c->eax = 0; > - c->ebx = signature[0]; > - c->ecx = signature[1]; > - c->edx = signature[2]; > + if (!cpu->no_kvm) { > + memcpy(signature, "KVMKVMKVM\0\0\0", 12); > + c = &cpuid_data.entries[cpuid_i++]; > + c->function = KVM_CPUID_SIGNATURE | kvm_base; > + c->eax = 0; > + c->ebx = signature[0]; > + c->ecx = signature[1]; > + c->edx = signature[2]; > > - c = &cpuid_data.entries[cpuid_i++]; > - c->function = KVM_CPUID_FEATURES | kvm_base; > - c->eax = env->features[FEAT_KVM]; > + c = &cpuid_data.entries[cpuid_i++]; > + c->function = KVM_CPUID_FEATURES | kvm_base; > + c->eax = env->features[FEAT_KVM]; > > - has_msr_async_pf_en = c->eax & (1 << KVM_FEATURE_ASYNC_PF); > + has_msr_async_pf_en = c->eax & (1 << KVM_FEATURE_ASYNC_PF); > > - has_msr_pv_eoi_en = c->eax & (1 << KVM_FEATURE_PV_EOI); > + has_msr_pv_eoi_en = c->eax & (1 << KVM_FEATURE_PV_EOI); > > - has_msr_kvm_steal_time = c->eax & (1 << KVM_FEATURE_STEAL_TIME); > + has_msr_kvm_steal_time = c->eax & (1 << KVM_FEATURE_STEAL_TIME); > + } > > cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused); > > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >