diff options
| author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2018-04-25 22:04:25 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-22 18:54:02 +0200 |
| commit | 97224b3da69810155b44f173cc8959eea565a98d (patch) | |
| tree | 8216eadca1d1fd01fc296587d0996f773cbf1fed | |
| parent | 716bfae3b3f40de8c0a6ae83f199d96fd152b3cc (diff) | |
x86/KVM/VMX: Expose SPEC_CTRL Bit(2) to the guest
commit da39556f66f5cfe8f9c989206974f1cb16ca5d7c upstream
Expose the CPUID.7.EDX[31] bit to the guest, and also guard against various
combinations of SPEC_CTRL MSR values.
The handling of the MSR (to take into account the host value of SPEC_CTRL
Bit(2)) is taken care of in patch:
KVM/SVM/VMX/x86/spectre_v2: Support the combination of guest and host IBRS
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 8 |
2 files changed, 6 insertions, 4 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 4f544f2a7b06..69cdad1df3f2 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -394,7 +394,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, /* cpuid 7.0.edx*/ const u32 kvm_cpuid_7_0_edx_x86_features = - F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) | + F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) | F(RDS) | F(ARCH_CAPABILITIES); /* all calls to cpuid_count() should be made on the same cpu */ diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 208b431244c1..7a00b5d3c645 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3294,7 +3294,8 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) case MSR_IA32_SPEC_CTRL: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_IBRS) && - !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL)) + !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) && + !guest_cpuid_has(vcpu, X86_FEATURE_RDS)) return 1; msr_info->data = to_vmx(vcpu)->spec_ctrl; @@ -3415,11 +3416,12 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) case MSR_IA32_SPEC_CTRL: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_IBRS) && - !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL)) + !guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) && + !guest_cpuid_has(vcpu, X86_FEATURE_RDS)) return 1; /* The STIBP bit doesn't fault even if it's not advertised */ - if (data & ~(SPEC_CTRL_IBRS | SPEC_CTRL_STIBP)) + if (data & ~(SPEC_CTRL_IBRS | SPEC_CTRL_STIBP | SPEC_CTRL_RDS)) return 1; vmx->spec_ctrl = data; |