On Wed, 05 May 2010 08:43:16 -0700, "Kevin D. Kissell" <firstname.lastname@example.org>
> >> I'm glad to hear that the patch is functional. It was pretty clear that
> >> it would solve your problem, but I was concerned that the inability to
> >> write the Cause bits was done as a way around some other problem.
> >> Someone went to a certain amount of trouble to not accept them as
> >> inputs, in violation of spec. I just looked back, and the bug was
> >> introduced as part of a patch of Ralf's from April 2005 entitled "Fix
> >> Preemption and SMP problems in the FP emulator". It's unlikely that
> >> overriding CTC semantics actually fixed any underlying problems, but it
> >> may have masked symptoms of problems that we can only hope have been
> >> fixed in the mean time. Anyone run this patch on an FPUless SMP? Oh,
> >> for a 34Kf with a bunch of TCs! ;o)
> > That's commit ID 72402ec9efdb2ea7e0ec6223cf20e7301a57da02 and the patch
> > was comitted during the CVS days which only records the comitter but not
> > the author. The actual author is Atsushi Nemoto.
> Well,. I certainly understood that you were simply the guy who did the
> commit. Didn't mean to make it sound like an accusation, but it was
> marginally easier to type your name and date than to find, cut, and
> paste the commit ID. Sorry if it came off wrong. It would be cool if
> Atsushi remembered the reasoning behind the change, but empirical proof
> that undoing it doesn't create a subtle problem for current SMP kernels
> would be better still.
Yes, that's my patch. Though I cannot remember precisely, maybe I
just had (mis)thought Cause bits in FCSR are read-only at that time.
I have never used real SMP MIPS platforms, so there must be no
I'm OK with Kevin's fix. Thank you very much for reporting and