Comment # 40 on bug 898395 from Bit Juggler

commit 9238f36a5a5097018b90baa42c473d2f916a46f5 - which seems to cause the
problem - is not very large. As far as i understand the information exposed by
"git show" there are only three files which were changed by this commit:

hci_core.h, hci_core.c and hci_event.c

Is it worth trying to just "undo" this single commit and then build and test a
kernel without these changes?

Naturally that will not work, if any changes introduced later rely on the
changes introduced with commit 9238f36a5a5097018b90baa42c473d2f916a46f5.

If you think its woth trying, then i would need some help on how to "undo" just
that single commit in my local repository.