CONFIG_CPU_COPY_FA is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CONFIG_CPU_COPY_FA (not configurable)

modulename: copypage-fa.ko

configname: CONFIG_CPU_COPY_FA

Linux Kernel Configuration
└─>CPU_COPY_FA
In linux kernel since version 2.6.30 (release Date: 2009-06-09)  
source code:
arch/arm/mm/copypage-fa.c
depends
CONFIG_MMU