On 03/03/20 19:01, Sean Christopherson wrote: > static bool cpuid_function_in_range(struct kvm_vcpu *vcpu, u32 function) > { > struct kvm_cpuid_entry2 *max; > > if (function >= 0x40000000 && function <= 0x4fffffff) > max = kvm_find_cpuid_entry(vcpu, function & 0xffffff00, 0); > else > max = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0); > return max && function <= max->eax; > } Yes, this is a good idea (except it should be & 0xc0000000 to cover Centaur). Paolo