diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index edf98f8588ee..2701497edda5 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -776,8 +776,13 @@ void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val)
 	rcu_read_lock();
 	memcg = memcg_from_slab_page(page);
 
-	/* Untracked pages have no memcg, no lruvec. Update only the node */
-	if (!memcg || memcg == root_mem_cgroup) {
+	/*
+	 * Untracked pages have no memcg, no lruvec. Update only the
+	 * node. If we reparent the slab objects to the root memcg,
+	 * when we free the slab object, we need to update the per-memcg
+	 * vmstats to keep it correct for the root memcg.
+	 */
+	if (!memcg) {
 		__mod_node_page_state(pgdat, idx, val);
 	} else {
 		lruvec = mem_cgroup_lruvec(pgdat, memcg);