--- a/mm/memcontrol.c~mm-memcg-slab-fix-return-child-memcg-objcg-for-root-memcg +++ a/mm/memcontrol.c @@ -2975,6 +2975,7 @@ __always_inline struct obj_cgroup *get_o objcg = rcu_dereference(memcg->objcg); if (objcg && obj_cgroup_tryget(objcg)) break; + objcg = NULL; } rcu_read_unlock();