On Fri, Sep 19, 2014 at 10:36 AM, H. Peter Anvin <[email protected]> wrote: > On 09/19/2014 10:21 AM, Andy Lutomirski wrote: >>> >>> There is a huge disadvantage to the fact that CPUID is a user space >>> instruction, though. >> >> We can always make cpuid on the leaf in question return all zeros if CPL > 0. >> > > Not sure that is better...
It's better than #GP... This is why I prefer rdmsr: the privilege semantics are already appropriate. Also, I wouldn't be surprised if shoehorning non-constant results into cpuid implementations might be awkward for some hypervisors. --Andy -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
