default or selected kernelversion does not have config value CONFIG_ARCH_HAS_UACCESS_MCSAFE.
Result is shown for kernelversion 6.9.9

CONFIG_ARCH_HAS_UACCESS_MCSAFE (not configurable)

configname: CONFIG_ARCH_HAS_UACCESS_MCSAFE

Linux Kernel Configuration
└─>Library routines
└─>ARCH_HAS_UACCESS_MCSAFE
In linux kernel since version 4.2 (release Date: 2015-08-30)