* Daniel Bristot de Oliveira | 2014-05-05 16:10:51 [-0300]:

Figure out why it was disabled is one objective of this RFC :-).

The patch first appeared in patch-3.2-rt10.patch. Haven't seen it in
v3.0-rt1 nor in in the first v3.2-rcX-rt1. I would assume that it was
something locking specific.
I haven't seen any lockdep splat in current v3.14-RT. Therefore I'm
going to drop that hunk from the patch so it can be enabled again.

Since I don't really know why it was disabled in v3.2 I think it is
best not to backport this change unless someone figures out the real
reason and provides proof that it works in the older kernel as well.

Sebastian