CONFIG_KVM_BOOK3S_HANDLER is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

CONFIG_KVM_BOOK3S_HANDLER (not configurable)

modulename: book3s_exports.ko

configname: CONFIG_KVM_BOOK3S_HANDLER

Linux Kernel Configuration
└─>Virtualization
└─>KVM_BOOK3S_HANDLER
In linux kernel since version 2.6.35 (release Date: 2010-08-01)  
source code:
arch/powerpc/kvm/book3s_exports.c