How do I reserve low memory (pre OS)?
Background: I need to reserve an amount of memory below 0xA0000 prior to my operating system starts. To do this I change the 0040:0013 (or 0x413) word which is the amount of low memory available in KiB. However, Windows and other operating systems use E820h/INT15h to query the memory layout and some BIOS:es doesn't reflect 0x413 changes...