Physical memory mapping padding


Linux Kernel Configuration
└─>Processor type and features
└─>Physical memory mapping padding
In linux kernel since version 4.1 (release Date: 2015-06-21)  
Define the padding in terabytes added to the existing physical
memory size during kernel memory randomization. It is useful
for memory hotplug support but reduces the entropy available for
address randomization.

If unsure, leave at the default value.