As per recent discussions spin_unlock_wait() has an unintuitive 'feature'. lkml.kernel.org/r/20160520053926.gc31...@linux-uzut.site
These patches pull the existing solution into generic code; annotate all spin_unlock_wait() users and fix nf_conntrack more. The alternative -- putting smp_acquire__after_ctrl_dep() into spin_unlock_wait() can be done later if desired, now that al users are audited and corrected. Please (very) carefully consider.
