Unaddressable device memory (GPU memory, ...)

configname: CONFIG_DEVICE_PRIVATE

Linux Kernel Configuration
└─>Unaddressable device memory (GPU memory, ...)
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Allows creation of struct pages to represent unaddressable device
memory; i.e., memory that is only accessible from the device (or
group of devices). You likely also want to select HMM_MIRROR.