[2/2] powerpc/sysfs: fix reference leak of cpu device_nodes present at boot

[Michael Ellerman]

On Tue, 2017-04-18 at 00:24:39 UTC, Tyrel Datwyler wrote:
> For cpus present at boot each logical cpu acquires a reference to the
> associated device node of the core. This happens in register_cpu() which
> is called by topology_init(). The result of this is that we end up with
> a reference held by each thread of the core. However, these references
> are never freed if the cpu core is dlpar removed.
> 
> This patch fixes the reference leaks by acquiring and releasing the
> references in the cpu hotplug callbacks un/register_cpu_online().
> With this patch symmetric reference counting is observed with both cpus
> present at boot, and those dlpar added after boot.
> 
> Cc: stable at vger.kernel.org
> fixes: f86e4718f24b ("driver/core: cpu: initialize of_node in cpu's device struture")
> Signed-off-by: Tyrel Datwyler <tyreld at linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/e76ca27790a514590af782f83f6eae

cheers