Re: [PATCH v5 1/2] KVM: X86: Introduce handle_ud()

[David Hildenbrand]

On 04.04.2018 19:12, Paolo Bonzini wrote:
> On 04/04/2018 13:54, David Hildenbrand wrote:
>>> +{
>>> +   enum emulation_result er;
>>> +
>>> +   er = emulate_instruction(vcpu, EMULTYPE_TRAP_UD);
>>> +   if (er == EMULATE_USER_EXIT)
>>> +           return 0;
>>> +   if (er != EMULATE_DONE)
>>> +           kvm_queue_exception(vcpu, UD_VECTOR);
>>> +   return 1;
>> I would now actually prefer
>>
>> if (er == EMULATE_DONE)
>>      return 1 ...
> 
> Why?  The return statement would be duplicated.
> 
> Paolo
> 

I was talking about two equality checks vs. 1 equality and 1 inequality
check.

er = emulate_instruction(vcpu, EMULTYPE_TRAP_UD);
if (er == EMULATE_USER_EXIT)
        return 0;
else if (er == EMULATE_DONE)
        return 1;
return kvm_queue_exception(vcpu, UD_VECTOR);


-- 

Thanks,

David / dhildenb