[PATCH] Add call to non-crashing cores through IPI

[Per Fransson]

>
> I wonder whether it is good idea to enable interrupts here? What
> if we came here from an interrupt handler with interrupts already
> disabled?
>
> I guess you did this because smp_call_function() needs to have
> interrupts enabled, right?
>

Yup, that's why I did it.

> As we still need to make sure that all the secondary CPUs are
> stopped, should we do just something like:
>
>        smp_send_stop();
>
> and then in ipi_cpu_stop() we check whether oops_in_progress is set
> and save the cpu state before entering that never-ending loop?

But we still need to wait for it to complete, right? Will smp_send_stop()
handle the requirements of the underlying ipi regardless of the initial state?

Regards,
Per