Re: Adding(?) XI support to MIPS-Linux?

[Brian Foster <brian.foster@innova-card.com>]

On Wednesday 18 June 2008 11:36:53 Kevin D. Kissell wrote:
> Brian Foster wrote:
> >  Whilst thinking about the problem and possible solutions,
> >  it occurred to me there could be a defect in the current
> >  trampoline:  Suppose there is a signal, either at point A,
> >  due to <instr> itself, or at point B, which is caught on
> >  this stack, and the user-land signal-handler ‘return’s.
> >
> >  Doesn't the signal-handler/sigreturn stack-frame overwrite
> >  the FP trampoline?   [ ... ]
> 
> When I first integrated the FP emulator into the kernel, back in 2.2.x,
> I seem to recall that someone found this problem and that I came up with
> a tweak to signal stack setup that protected the FP branch delay slot
> trampoline.  Maybe I'm mistaken, or maybe the tweak was lost?

 The error is mine:  I overlooked the tweak.
 Now that you mention it / remind me of it,
 I distinctly recall it; in fact, that was
 what first alerted me to the existance of
 the FP trampoline.

sorry & cheers!
        -blf-
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