On Thu, Jan 06, 2000 at 04:19:27PM +0100, Kevin D. Kissell wrote:
> >If that's desired, how about providing a syscall which allows to manipulate
> >this and possibly other bits?
> I very much prefer the idea of having exec() to the right thing, so
> that 32/32 fpr and o32 ABI programs can be mixed and matched
> as appropriate - assuming, of course, that there's sufficient information
> in the binary header to do the job! In practical terms, given that
> Linux is a multiuser and multitasking system, a syscall that throws
> some sort of global switch could only be safely invoked once
> at boot time, and as such offers little advantage over hardwired
> kernel code.
I was suggesting such a syscall because embedded people have asked me about
making the 32/32 fpr model available to `normal' o32 code. N32 won't work
for them for practical reasons (linker tooo buggy) and 64-bit ABI is
unacceptable for size / tlb / cache reasons.
For the general case you're of course right, exec() should do the right
thing. And modulo the bug we're discussing here the 32-bit kernel already
does the right thing to handle the general case.