A glance at the EFI loader's source found this
Code:
// failsafe, don't report our own structures as free
if( mement->NumberOfPages==0 ||
((mement->PhysicalStart <= (UINT64)bootboot &&
mement->PhysicalStart+(mement->NumberOfPages*PAGESIZE) > (UINT64)bootboot) ||
(mement->PhysicalStart <= (UINT64)env.ptr &&
mement->PhysicalStart+(mement->NumberOfPages*PAGESIZE) > (UINT64)env.ptr) ||
(mement->PhysicalStart <= (UINT64)initrd.ptr &&
mement->PhysicalStart+(mement->NumberOfPages*PAGESIZE) > (UINT64)initrd.ptr) ||
(mement->PhysicalStart <= (UINT64)core.ptr &&
mement->PhysicalStart+(mement->NumberOfPages*PAGESIZE) > (UINT64)core.ptr) ||
(mement->PhysicalStart <= (UINT64)paging &&
mement->PhysicalStart+(mement->NumberOfPages*PAGESIZE) > (UINT64)paging)
)) {
continue;
}
I guess it just ignores the bootloader's structures and doesn't put them in the map if I'm not mistaken. Now, it would be best practice to do what Limine does and create entries specifically for this kind of memory, so that the kernel can reclaim some of it when its done using the bootloader.
Full source is at
https://gitlab.com/bztsrc/bootboot/-/blob/master/x86_64-efi/bootboot.c in case I missed something.