memory address (this means in some cases it can also include PCI memory
holes).
-We map EFI runtime services in the 'efi_pgd' PGD in a 64Gb large virtual
+We map EFI runtime services in the 'efi_pgd' PGD in a 64GB large virtual
memory window (this size is arbitrary, it can be raised later if needed).
The mappings are not part of any other kernel PGD and are only available
during EFI runtime calls.