Re: [Etherboot-developers] Mknbi is the misbehaving when reloc'd

[Eric W B. <ebi...@ln...>]

Marc Singer <el...@bu...> writes:

> > For absolute references I just prefer pointer arithematic.  Segment
> > loads are expensive.  But you very rarely if ever need absolute references.
> 
> Segment loads are expensive, references are cheap.  If you leave them
> loaded then your only penalty is the segment prefix.  And since the
> occurrence of absolute memory references is low, there is little
> reason not to use segments except that most people aren't comfortable
> with them.  %^)

Two other reasons.
It is awkward to do from C.
And you cannot use segments when talking to devices virt_to_bus/bus_to_virt...

My goal when I changed etherboot was to use a C api that is portable.
So I did not even consider special purpose things like a copy_from_absolute.

Eric