CONFIG_KVM_BOOK3S_64_HV is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

KVM for POWER7 and later using hypervisor mode in host

modulename: kvm-hv.ko

configname: CONFIG_KVM_BOOK3S_64_HV

Linux Kernel Configuration
└─>KVM for POWER7 and later using hypervisor mode in host
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Support running unmodified book3s_64 guest kernels in
virtual machines on POWER7 and newer processors that have
hypervisor mode available to the host.

If you say Y here, KVM will use the hardware virtualization
facilities of POWER7 (and later) processors, meaning that
guest operating systems will run at full hardware speed
using supervisor and user modes. However, this also means
that KVM is not usable under PowerVM (pHyp), is only usable
on POWER7 or later processors, and cannot emulate a
different processor from the host processor.

If unsure, say N.

source code: