DOSFS is not 4Kn compatible

DOSFS has a static sector size of 512 bytes here and here and fails to recognise FAT partitions if the BPB BytesPerSec is not 512.

Although using a static 512 bytes to read the FAT header is fine, once the FAT header is validated all further access should be using BytesPerSec from the BPB for the sector size.

EDIT: Forgot to mention that this will prevent Pi’s, PineBook and any other OS build that relies on a FAT bootloader partition from booting correctly on a 4Kn drive