Resolved conflict in kernel/sched/core.c using Peter Zijlstra's
approach from https://lkml.org/lkml/2012/9/5/585.
                migrate_tasks(cpu);
                BUG_ON(rq->nr_running != 1); /* the migration thread */
                raw_spin_unlock_irqrestore(&rq->lock, flags);
 +              break;
  
-               {
-                       struct rq *dest_rq;
- 
-                       local_irq_save(flags);
-                       dest_rq = cpu_rq(smp_processor_id());
-                       raw_spin_lock(&dest_rq->lock);
-                       calc_load_migrate(rq);
-                       raw_spin_unlock_irqrestore(&dest_rq->lock, flags);
-               }
 +      case CPU_DEAD:
+               calc_load_migrate(rq);
                break;
  #endif
        }