default or selected kernelversion does not have config value CONFIG_ARCH_THREAD_INFO_ALLOCATOR.
Result is shown for kernelversion 6.5.1

CONFIG_ARCH_THREAD_INFO_ALLOCATOR (not configurable)

configname: CONFIG_ARCH_THREAD_INFO_ALLOCATOR

Linux Kernel Configuration
└─>ARCH_THREAD_INFO_ALLOCATOR
In linux kernel since version 3.1 (release Date: 2011-10-24)