On Thu, May 01, 2014 at 12:02:49PM -0700, Andy Lutomirski wrote: > > Is RDSEED really reasonable here? Won't it slow down by several > orders of magnitude? That is I think the biggest problem; RDRAND and RDSEED are fast if they are native, but they will involve a VM exit if they need to be emulated. So when an OS might want to use RDRAND and RDSEED might be quite different if we know they are being emulated. Using the RDRAND and RDSEED "api" certainly makes sense, at least for x86, but I suspect we might want to use a different way of signalling that a VM guest can use RDRAND and RDSEED if they are running on a CPU which doesn't provide that kind of access. Maybe a CPUID extended function parameter, if one could be allocated for use by a Linux hypervisor? - Ted -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
