Clear any CPUs going offline from the idle mask to prevent tasks trying to
schedule onto them.

-ck

---
 kernel/sched/bfs.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Index: linux-4.7-ck4/kernel/sched/bfs.c
===================================================================
--- linux-4.7-ck4.orig/kernel/sched/bfs.c	2016-09-13 17:21:54.034208821 +1000
+++ linux-4.7-ck4/kernel/sched/bfs.c	2016-09-13 17:21:54.032208866 +1000
@@ -5773,8 +5773,11 @@ static void set_rq_online(struct rq *rq)
 static void set_rq_offline(struct rq *rq)
 {
 	if (rq->online) {
-		cpumask_clear_cpu(cpu_of(rq), rq->rd->online);
+		int cpu = cpu_of(rq);
+
+		cpumask_clear_cpu(cpu, rq->rd->online);
 		rq->online = false;
+		clear_cpuidle_map(cpu);
 	}
 }