machdep.hlt_cpus not safe with ULE?

Andriy Gapon avg at
Mon Feb 21 16:29:27 UTC 2011

on 19/02/2011 14:36 Steven Hartland said the following:
> I'm trying to debug a possibly failing CPU, so I thought it would
> be easy just disable the cores using machdep.hlt_cpus and see if
> we see the panic's we've been seeing.
> The problem is it seems ULE doesnt properly support machdep.hlt_cpus
> and still schedules processes onto the halted cpus which obviously
> causes problems.
> Can anyone confirm this behaviour?

Yes, your observations are correct.
Please also see:

> Should machdep.hlt_cpus and I assume
> the logical counterpart never be used with ULE?

Andriy Gapon

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