[PATCH] cxl: Fix reference count on struct pid when attaching

[Michael Ellerman]

On Thu, 2015-10-29 at 13:39 +0100, Frederic Barrat wrote:

> When the cxl driver creates a context, it stores the pid of the
> calling task, incrementing the reference count on the struct
> pid. Current code mistakenly increments the reference count twice,
> once through get_task_pid(), once through get_pid(). The reference
> count is only decremented once on detach, thus the struct pid of the
> task attaching is never freed. The fix is to simply remove the call to
> get_pid().
> 
> Signed-off-by: Frederic Barrat <frederic.barrat at fr.ibm.com>

What's the symptom?
Broken since when?
Forever?
So should go to stable?
Starting from which release?

cheers