[PATCH resend] MIPS: Allow FPU emulator to use non-stack area.

[Rich Felker]

On Tue, Oct 07, 2014 at 12:16:59PM -0700, Leonid Yegoshin wrote:
> On 10/07/2014 12:09 PM, Rich Felker wrote:
> >I agree completely here. We should not break things (or, as it
> >seems, leave them broken) for common usage cases that affect
> >everyone just to coddle proprietary vendor-specific instructions.
> >The latter just should not be used in delay slots unless the chip
> >vendor also promises to provide fpu branch in hardware. Rich
> And what do you propose - remove a current in-stack emulation and
> you still think it doesn't break a status-quo?

The in-stack trampoline support could be left but used only for
emulating instructions the kernel doesn't know. This would make all
normal binaries immediately usable with non-executable stack, and
would avoid the only potential source of regressions. Ultimately I
think the "xol" stuff should be removed, but that could be a long term
goal.

Rich