ddt.offset confusingly commented

[boeckmann]

https://github.com/FDOS/kernel/blob/master/hdr/device.h#L239 states that ddt.offset is the relative partition offset. But in fact this seems to be the absolute LBA sector number of the first sector of the partition.

Initialized here:

kernel/kernel/initdisk.c

Line 576 in 8552d83

pddt->ddt_offset = StartSector;

This is in contrast to bpb_hidden, which is relative to the "container", either the start of the disk or the start of the extended partition:

kernel/kernel/initdisk.c

Line 582 in 8552d83

pddt->ddt_defbpb.bpb_hidden = pEntry->RelSect;

[PerditionC]

I can see that, partition offset relative to start of disk, but absolute lba of start of partition is clearer.