KVM: x86: introduce kvm_supported_xcr0()

[deliverable/linux.git] / arch / x86 / kvm / cpuid.c

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index ddc8a7e165df2857b66859b391048dc209049a67..18aefb4d0927258c434baf777ac757e5baee4faa 100644 (file)
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -43,6 +43,16 @@ static u32 xstate_required_size(u64 xstate_bv)
        return ret;
 }
 
+u64 kvm_supported_xcr0(void)
+{
+       u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
+
+       if (!kvm_x86_ops->mpx_supported || !kvm_x86_ops->mpx_supported())
+               xcr0 &= ~(XSTATE_BNDREGS | XSTATE_BNDCSR);
+
+       return xcr0;
+}
+
 void kvm_update_cpuid(struct kvm_vcpu *vcpu)
 {
        struct kvm_cpuid_entry2 *best;
@@ -73,7 +83,7 @@ void kvm_update_cpuid(struct kvm_vcpu *vcpu)
        } else {
                vcpu->arch.guest_supported_xcr0 =
                        (best->eax | ((u64)best->edx << 32)) &
-                       host_xcr0 & KVM_SUPPORTED_XCR0;
+                       kvm_supported_xcr0();
                vcpu->arch.guest_xstate_size = best->ebx =
                        xstate_required_size(vcpu->arch.xcr0);
        }
@@ -210,13 +220,6 @@ static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
        entry->flags = 0;
 }
 
-static bool supported_xcr0_bit(unsigned bit)
-{
-       u64 mask = ((u64)1 << bit);
-
-       return mask & KVM_SUPPORTED_XCR0 & host_xcr0;
-}
-
 #define F(x) bit(X86_FEATURE_##x)
 
 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
@@ -439,16 +442,18 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
        }
        case 0xd: {
                int idx, i;
+               u64 supported = kvm_supported_xcr0();
 
-               entry->eax &= host_xcr0 & KVM_SUPPORTED_XCR0;
-               entry->edx &= (host_xcr0 & KVM_SUPPORTED_XCR0) >> 32;
+               entry->eax &= supported;
+               entry->edx &= supported >> 32;
                entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
                for (idx = 1, i = 1; idx < 64; ++idx) {
+                       u64 mask = ((u64)1 << idx);
                        if (*nent >= maxnent)
                                goto out;
 
                        do_cpuid_1_ent(&entry[i], function, idx);
-                       if (entry[i].eax == 0 || !supported_xcr0_bit(idx))
+                       if (entry[i].eax == 0 || !(supported & mask))
                                continue;
                        entry[i].flags |=
                               KVM_CPUID_FLAG_SIGNIFCANT_INDEX;