Re: 32-bit ABI

[Ralf Baechle <ralf@linux-mips.org>]

On Sat, Apr 24, 2004 at 09:46:46AM +0200, Stanislaw Skowronek wrote:

> > > Ah, so it's like that. Great. Is the ELF64 support still not correct?
> > No, it's supposed to be working now.
> 
> OK. File it away under 'compatibility cruft' then ;)

The size difference this makes is still very significant.  In case of an
IP27 kernel default config:

   text    data     bss     dec     hex filename
2626662  747232  165760 3539654  3602c6 vmlinux
2907645 1283808  165760 4357213  427c5d vmlinux

The first kernel was built with the stock Makefile; the second was modified
to use 64-bit ELF using gcc 2.95.4 / binutils 2.13.2.1.  So I'd call those
817559 bytes kernel obesity ;)

> > > Well, as far as I know, and I'm probably right, it _does_ have some memory
> > > there. A whopping 16 kilobytes of memory mirrored by the HEART to allow
> > > placing exception vectors there (what a weird idea).
> > That's what the processor expects.
> 
> Yeah. The weirdness is not in that part; what's weird is placing the rest
> of memory somewhere else.

Not uncommon on SGI systems.  The Indy's memory also starts at 128MB; only
a few kB for exeption vectors are mirrored to physical address 0.

  Ralf