KVM: VMX: reset CPL only on CS register write.

Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

arch/x86/kvm/vmx.c

@@ -3269,7 +3269,8 @@ static void vmx_set_segment(struct kvm_vcpu *vcpu,
 	const struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
 
 	vmx_segment_cache_clear(vmx);
-	__clear_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail);
+	if (seg == VCPU_SREG_CS)
+		__clear_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail);
 
 	if (vmx->rmode.vm86_active && seg != VCPU_SREG_LDTR) {
 		vmx->rmode.segs[seg] = *var;