RE: [PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL

2021-01-04 Thread Babu Moger
> jmatt...@google.com > Subject: Re: [PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL > > On Wed, Dec 30, 2020, Borislav Petkov wrote: > > On Tue, Dec 22, 2020 at 04:31:55PM -0600, Babu Moger wrote: > > > @@ -2549,7 +2559,10 @@ static int

RE: [PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL

2021-01-04 Thread Babu Moger
oogle.com > Subject: Re: [PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL > > On 12/22/20 4:31 PM, Babu Moger wrote: > > Newer AMD processors have a feature to virtualize the use of the > > SPEC_CTRL MSR. A hypervisor may wish to impose speculation controls on

Re: [PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL

2021-01-04 Thread Tom Lendacky
On 12/22/20 4:31 PM, Babu Moger wrote: Newer AMD processors have a feature to virtualize the use of the SPEC_CTRL MSR. A hypervisor may wish to impose speculation controls on guest execution or a guest may want to impose its own speculation controls. Therefore, the processor implements both host

Re: [PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL

2020-12-30 Thread Sean Christopherson
On Wed, Dec 30, 2020, Borislav Petkov wrote: > On Tue, Dec 22, 2020 at 04:31:55PM -0600, Babu Moger wrote: > > @@ -2549,7 +2559,10 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct > > msr_data *msr_info) > > !guest_cpuid_has(vcpu, X86_FEATURE_AMD_SSBD)) > >

Re: [PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL

2020-12-29 Thread Borislav Petkov
On Tue, Dec 22, 2020 at 04:31:55PM -0600, Babu Moger wrote: > @@ -2549,7 +2559,10 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct > msr_data *msr_info) > !guest_cpuid_has(vcpu, X86_FEATURE_AMD_SSBD)) > return 1; > > - msr_info->data =

[PATCH v2 2/2] KVM: SVM: Add support for Virtual SPEC_CTRL

2020-12-22 Thread Babu Moger
Newer AMD processors have a feature to virtualize the use of the SPEC_CTRL MSR. A hypervisor may wish to impose speculation controls on guest execution or a guest may want to impose its own speculation controls. Therefore, the processor implements both host and guest versions of SPEC_CTRL.