diff --git a/kernel/fork.c b/kernel/fork.c
index dcf1f9c655d84a4b0944146438468db17d87ef44..9b1ea79deaa52ee5d6c56390264216e6f86c42cc 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -953,6 +953,10 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
 	tsk->prefer_cpus = NULL;
 #endif
 
+#ifdef CONFIG_QOS_SCHED_SMART_GRID
+	tsk->grid_qos = NULL;
+#endif
+
 #ifdef CONFIG_SCHED_TASK_RELATIONSHIP
 	tsk->rship = NULL;
 #endif
diff --git a/kernel/sched/grid/qos.c b/kernel/sched/grid/qos.c
index 7ee3687347cee0ab58b1f526cc927081ee6d74a7..60b1ff843bbb969a41a5b9ba8295f582801ce9ec 100644
--- a/kernel/sched/grid/qos.c
+++ b/kernel/sched/grid/qos.c
@@ -70,6 +70,9 @@ int sched_grid_qos_fork(struct task_struct *p, struct task_struct *orig)
 
 void sched_grid_qos_free(struct task_struct *p)
 {
+	if (!p->grid_qos)
+		return;
+
 	kfree(p->grid_qos);
 	p->grid_qos = NULL;
 }