KVM: x86: mask CPUID(0xD,0x1).EAX against host value

This ensures that the guest doesn't see XSAVE extensions
(e.g. xgetbv1 or xsavec) that the host lacks.

Cc: stable@vger.kernel.org
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 8efb839948e5..bbbaa802d13e 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -534,6 +534,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
                         do_cpuid_1_ent(&entry[i], function, idx);
                         if (idx == 1) {
                                 entry[i].eax &= kvm_cpuid_D_1_eax_x86_features;
+                                cpuid_mask(&entry[i].eax, CPUID_D_1_EAX);
                                 entry[i].ebx = 0;
                                 if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
                                         entry[i].ebx =