[PATCH] powerpc/irq: Improve/fix migrate_irqs()

[Benjamin Herrenschmidt]

On Wed, 2017-02-08 at 21:02 +1100, Michael Ellerman wrote:
> Benjamin Herrenschmidt <benh at kernel.crashing.org> writes:
> 
> > migrate_irqs() is used by some platforms to migrate interrupts
> > away from a CPU about to be offlined.
> > 
> > The current implementation had various issues such as not taking
> > the descriptor lock before manipulating it.
> 
> ... and not checking for a NULL chip (but presumably that's never
> happened), and always calling irq_set_affinity() even for IRQs not on
> the CPU.
> 
> But, any reason we can't use irq_migrate_all_off_this_cpu() ?
> Which is in generic code.

Nope, I didn't notice it. I'll give that a spin.

Cheers,
Ben.