1 files changed, 35 insertions, 11 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 93a7e36ded89..dd39ba000b31 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1055,12 +1055,24 @@ struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
 				      struct mem_cgroup *memcg)
 {
 	struct mem_cgroup_per_zone *mz;
+	struct lruvec *lruvec;
 
-	if (mem_cgroup_disabled())
-		return &zone->lruvec;
+	if (mem_cgroup_disabled()) {
+		lruvec = &zone->lruvec;
+		goto out;
+	}
 
 	mz = mem_cgroup_zoneinfo(memcg, zone_to_nid(zone), zone_idx(zone));
-	return &mz->lruvec;
+	lruvec = &mz->lruvec;
+out:
+	/*
+	 * Since a node can be onlined after the mem_cgroup was created,
+	 * we have to be prepared to initialize lruvec->zone here;
+	 * and if offlined then reonlined, we need to reinitialize it.
+	 */
+	if (unlikely(lruvec->zone != zone))
+		lruvec->zone = zone;
+	return lruvec;
 }
 
 /*
@@ -1087,9 +1099,12 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct zone *zone)
 	struct mem_cgroup_per_zone *mz;
 	struct mem_cgroup *memcg;
 	struct page_cgroup *pc;
+	struct lruvec *lruvec;
 
-	if (mem_cgroup_disabled())
-		return &zone->lruvec;
+	if (mem_cgroup_disabled()) {
+		lruvec = &zone->lruvec;
+		goto out;
+	}
 
 	pc = lookup_page_cgroup(page);
 	memcg = pc->mem_cgroup;
@@ -1107,7 +1122,16 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct zone *zone)
 		pc->mem_cgroup = memcg = root_mem_cgroup;
 
 	mz = page_cgroup_zoneinfo(memcg, page);
-	return &mz->lruvec;
+	lruvec = &mz->lruvec;
+out:
+	/*
+	 * Since a node can be onlined after the mem_cgroup was created,
+	 * we have to be prepared to initialize lruvec->zone here;
+	 * and if offlined then reonlined, we need to reinitialize it.
+	 */
+	if (unlikely(lruvec->zone != zone))
+		lruvec->zone = zone;
+	return lruvec;
 }
 
 /**
@@ -3697,17 +3721,17 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
 static bool mem_cgroup_force_empty_list(struct mem_cgroup *memcg,
 				int node, int zid, enum lru_list lru)
 {
-	struct mem_cgroup_per_zone *mz;
+	struct lruvec *lruvec;
 	unsigned long flags, loop;
 	struct list_head *list;
 	struct page *busy;
 	struct zone *zone;
 
 	zone = &NODE_DATA(node)->node_zones[zid];
-	mz = mem_cgroup_zoneinfo(memcg, node, zid);
-	list = &mz->lruvec.lists[lru];
+	lruvec = mem_cgroup_zone_lruvec(zone, memcg);
+	list = &lruvec->lists[lru];
 
-	loop = mz->lru_size[lru];
+	loop = mem_cgroup_get_lru_size(lruvec, lru);
 	/* give some margin against EBUSY etc...*/
 	loop += 256;
 	busy = NULL;
@@ -4745,7 +4769,7 @@ static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node)
 
 	for (zone = 0; zone < MAX_NR_ZONES; zone++) {
 		mz = &pn->zoneinfo[zone];
-		lruvec_init(&mz->lruvec, &NODE_DATA(node)->node_zones[zone]);
+		lruvec_init(&mz->lruvec);
 		mz->usage_in_excess = 0;
 		mz->on_tree = false;
 		mz->memcg = memcg;