[RFC] powerpc/xive: Remove irq from queue when it is shutdown

[Benjamin Herrenschmidt]

On Wed, 2018-03-14 at 18:47 +0100, Cédric Le Goater wrote:
> We could also loop on the ESB 'P' bit to wait for the irqs to be handled,
> using :
> 
>         xive_esb_read(irq, XIVE_ESB_GET)
> 
> which has no side effect. It looks simpler to me. Is that possible ? 

But you can race with something sending another one... I prefer the
guarantee that after final masking, we check the queue contents on
shutdown.

That will be solid vs. other type of interrupts as well.

Cheers,
Ben.