[PATCH] powerpc: xive: ensure active irqd when setting affinity

[Michael Ellerman]

Sukadev Bhattiprolu <sukadev at linux.vnet.ibm.com> writes:

> From fd0abf5c61b6041fdb75296e8580b86dc91d08d6 Mon Sep 17 00:00:00 2001
> From: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> Date: Tue, 1 Aug 2017 20:54:41 -0500
> Subject: [PATCH] powerpc: xive: ensure active irqd when setting affinity
>
> Ensure irqd is active before attempting to set affinity. This should
> make the set affinity code more robust. For instance, this prevents
> these messages seen on a 4.12 based kernel when taking cpus offline:
>
>    [  123.053037264,3] XIVE[ IC 00  ] ISN 2 lead to invalid IVE !
>    [   77.885859] xive: Error -6 reconfiguring irq 17
>    [   77.885862] IRQ17: set affinity failed(-6).
>
> The underlying problem with taking cpus offline was fixed in 4.13-rc1 by:
>
>    commit 91f26cb4cd3c ("genirq/cpuhotplug: Do not migrated shutdown irqs")

So do we still need this? Or is the above only a partial fix?

I'm a bit confused.

cheers