KVM: x86: use Intel speculation bugs and features as derived in generic x86 code

commit 0c54914d0c52a15db9954a76ce80fee32cf318f4 upstream.

Similar to AMD bits, set the Intel bits from the vendor-independent
feature and bug flags, because KVM_GET_SUPPORTED_CPUID does not care
about the vendor and they should be set on AMD processors as well.

Suggested-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 6531ffcb174bd24d26496b5936411655fbedb083..90ad3c2db24acbd499fb4f83a5557188092b06ab 100644 (file)
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -395,6 +395,13 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
                        entry->ebx |= F(TSC_ADJUST);
                        entry->edx &= kvm_cpuid_7_0_edx_x86_features;
                        cpuid_mask(&entry->edx, 10);
+                       if (boot_cpu_has(X86_FEATURE_IBPB) &&
+                           boot_cpu_has(X86_FEATURE_IBRS))
+                               entry->edx |= F(SPEC_CTRL);
+                       if (boot_cpu_has(X86_FEATURE_STIBP))
+                               entry->edx |= F(INTEL_STIBP);
+                       if (boot_cpu_has(X86_FEATURE_SSBD))
+                               entry->edx |= F(SPEC_CTRL_SSBD);
                        /*
                         * We emulate ARCH_CAPABILITIES in software even
                         * if the host doesn't support it.

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 62f4e56fd350baca41b16062dcdc17990280a449..6275494c7ee08c5069c466e46218584a566bcfdf 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -917,8 +917,16 @@ u64 kvm_get_arch_capabilities(void)
 
        rdmsrl_safe(MSR_IA32_ARCH_CAPABILITIES, &data);
 
+       if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN))
+               data |= ARCH_CAP_RDCL_NO;
+       if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
+               data |= ARCH_CAP_SSB_NO;
+       if (!boot_cpu_has_bug(X86_BUG_MDS))
+               data |= ARCH_CAP_MDS_NO;
+
        return data;
 }
+
 EXPORT_SYMBOL_GPL(kvm_get_arch_capabilities);
 
 bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer)