[hppa-linux] memory layout
Thu, 18 Mar 1999 10:24:19 +0000 (GMT)
> Talking about only pa1.1 or 32 bit CPUs, I would say the same layout
> can be used as Linux on Intel does. That is kernel mapped at 0xc0000000.
> So 3 Gig for User space and 1 Gig for kernel. Of course, other ppl may
> have different ideas.
If you want to run PH/UX binaries then you need to probably follow their
> PA has this strange concept of Spaces and they have those
> space registers %sr0 to %sr7. This reminds me of Intel's segment
> registers. And whoever wanted to do any serious OS like Unix on 80386
> never liked segments.
Spaces is more segments done right. The reason we dont use segmentation
to split user/kernel on x86 any more is simply performance - it costs us
1 clock per dword copied to/from luser space.
The m68k people use the 'spaces' equivalent on the m68k quite heavily