Re: Tester with IP27/IP30 needed

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

On Tue, Jan 22, 2008 at 10:20:06AM -0500, Kumba wrote:

> No effect on Octane R14000A, as far as lockups.  Spikes the CPU usage in 'ps
> aux', but that's about it.

So far it seems R12000 and R14000 are unaffected.

> If I can get my plucky IP32 R10K to boot again soon, I may try it there for
> kicks and giggles.  Maybe we're also seeing a side effect of the R10K's spec
> exec knocking the non-cache-coherent machines out?
>
> Also, tried building the code with the R10K cache barrier on to see if anything
> else changes?  Generally reserved for kernel stuff, but Peter once speculated
> userland might have a use for it.

It's a cache instruction so priviledged which means userspace can't execute
it.  It's also entirely unclear if a cache barrier instruction would make a
difference at all.

  Ralf