* Steven Rostedt | 2015-01-21 15:13:52 [-0500]:

On Wed, 14 Jan 2015 15:11:38 -0600
"Brad Mouring" [off-list ref] wrote:

quoted

In task_blocks_on_lock, there's a null check on pi_blocked_on
of the task_struct. This pointer can encode the fact that the
task that contains the pointer is waking (preventing requeuing)
and therefore is non-null. Use the inline function to avoid
dereferencing an invalid "pointer"

Yep, this looks legit. I can apply it to the series I maintain.

I added it to v3.18 with a stable tag. I don't know why this did not
pop-up earlier or if this is part of the rtmutex re-write.

-- Steve

Sebastian