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

Workaround for I-Cache line size mismatch between CPU cores

configname: CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND

Linux Kernel Configuration
└─>Workaround for I-Cache line size mismatch between CPU cores
In linux kernel since version 5.1 (release Date: 2019-05-05)  
Some big.LITTLE systems have I-Cache line size mismatch between
LITTLE and big cores. Say Y here to enable a workaround for
proper I-Cache support on such systems. If unsure, say N.