1 files changed, 13 insertions, 5 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c52ec893e241..2bd7541d7c11 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -466,6 +466,8 @@ static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page)
         struct mem_cgroup_tree_per_node *mctz;
 
         mctz = soft_limit_tree_from_page(page);
+        if (!mctz)
+                return;
         /*
          * Necessary to update all ancestors when hierarchy is used.
          * because their event counter is not touched.
@@ -503,7 +505,8 @@ static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg)
         for_each_node(nid) {
                 mz = mem_cgroup_nodeinfo(memcg, nid);
                 mctz = soft_limit_tree_node(nid);
-                mem_cgroup_remove_exceeded(mz, mctz);
+                if (mctz)
+                        mem_cgroup_remove_exceeded(mz, mctz);
         }
 }
 
@@ -2558,7 +2561,7 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
          * is empty. Do it lockless to prevent lock bouncing. Races
          * are acceptable as soft limit is best effort anyway.
          */
-        if (RB_EMPTY_ROOT(&mctz->rb_root))
+        if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root))
                 return 0;
 
         /*
@@ -4135,17 +4138,22 @@ static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
         kfree(memcg->nodeinfo[node]);
 }
 
-static void mem_cgroup_free(struct mem_cgroup *memcg)
+static void __mem_cgroup_free(struct mem_cgroup *memcg)
 {
         int node;
 
-        memcg_wb_domain_exit(memcg);
         for_each_node(node)
                 free_mem_cgroup_per_node_info(memcg, node);
         free_percpu(memcg->stat);
         kfree(memcg);
 }
 
+static void mem_cgroup_free(struct mem_cgroup *memcg)
+{
+        memcg_wb_domain_exit(memcg);
+        __mem_cgroup_free(memcg);
+}
+
 static struct mem_cgroup *mem_cgroup_alloc(void)
 {
         struct mem_cgroup *memcg;
@@ -4196,7 +4204,7 @@ static struct mem_cgroup *mem_cgroup_alloc(void)
 fail:
         if (memcg->id.id > 0)
                 idr_remove(&mem_cgroup_idr, memcg->id.id);
-        mem_cgroup_free(memcg);
+        __mem_cgroup_free(memcg);
         return NULL;
 }