CONFIG_UNACCEPTED_MEMORY (not configurable)

modulename: unaccepted_memory.ko

configname: CONFIG_UNACCEPTED_MEMORY

Linux Kernel Configuration
└─>Device Drivers
└─>Firmware Drivers
└─>EFI (Extensible Firmware Interface) Support
└─>UNACCEPTED_MEMORY
In linux kernel since version 4.14.326 (release Date: 2023-09-23)  
Some Virtual Machine platforms, such as Intel TDX, require
some memory to be "accepted" by the guest before it can be used.
This mechanism helps prevent malicious hosts from making changes
to guest memory.

UEFI specification v2.9 introduced EFI_UNACCEPTED_MEMORY memory type.

This option adds support for unaccepted memory and makes such memory
usable by the kernel.

source code: