diff --git a/internal/querynode/scheduler_policy.go b/internal/querynode/scheduler_policy.go
index de60d12770..2ba5172765 100644
--- a/internal/querynode/scheduler_policy.go
+++ b/internal/querynode/scheduler_policy.go
@@ -9,7 +9,9 @@ type scheduleReadTaskPolicy func(sqTasks *list.List, targetUsage int32) ([]readT
 func defaultScheduleReadPolicy(sqTasks *list.List, targetUsage int32) ([]readTask, int32) {
 	var ret []readTask
 	usage := int32(0)
-	for e := sqTasks.Front(); e != nil; e = e.Next() {
+	var next *list.Element
+	for e := sqTasks.Front(); e != nil; e = next {
+		next = e.Next()
 		t, _ := e.Value.(readTask)
 		tUsage := t.CPUUsage()
 		if usage+tUsage > targetUsage {
diff --git a/internal/querynode/task_scheduler.go b/internal/querynode/task_scheduler.go
index a3cbf7ac31..5453132238 100644
--- a/internal/querynode/task_scheduler.go
+++ b/internal/querynode/task_scheduler.go
@@ -139,7 +139,9 @@ func (s *taskScheduler) tryEvictUnsolvedReadTask(headCount int) {
 		return
 	}
 	timeoutErr := fmt.Errorf("deadline exceed")
-	for e := s.unsolvedReadTasks.Front(); e != nil; e = e.Next() {
+	var next *list.Element
+	for e := s.unsolvedReadTasks.Front(); e != nil; e = next {
+		next = e.Next()
 		t, ok := e.Value.(readTask)
 		if !ok {
 			s.unsolvedReadTasks.Remove(e)
@@ -157,7 +159,8 @@ func (s *taskScheduler) tryEvictUnsolvedReadTask(headCount int) {
 	}
 	metrics.QueryNodeEvictedReadReqCount.WithLabelValues(fmt.Sprint(Params.QueryNodeCfg.GetNodeID())).Add(float64(diff))
 	busyErr := fmt.Errorf("server is busy")
-	for e := s.unsolvedReadTasks.Front(); e != nil && diff > 0; e = e.Next() {
+	for e := s.unsolvedReadTasks.Front(); e != nil && diff > 0; e = next {
+		next = e.Next()
 		diff--
 		s.unsolvedReadTasks.Remove(e)
 		t, ok := e.Value.(readTask)
@@ -316,7 +319,9 @@ func (s *taskScheduler) Close() {
 }
 
 func (s *taskScheduler) tryMergeReadTasks() {
-	for e := s.unsolvedReadTasks.Front(); e != nil; e = e.Next() {
+	var next *list.Element
+	for e := s.unsolvedReadTasks.Front(); e != nil; e = next {
+		next = e.Next()
 		t, ok := e.Value.(readTask)
 		if !ok {
 			s.unsolvedReadTasks.Remove(e)