Add logging if container or pod fails to be killed

pkg/kubelet/kubelet.go

@@ -1524,6 +1524,8 @@ func (kl *Kubelet) syncPod(o syncPodOptions) error {
 		if !pcm.Exists(pod) && !firstSync {
 			if err := kl.killPod(pod, nil, podStatus, nil); err == nil {
 				podKilled = true
+			} else {
+				klog.Errorf("killPod for pod %q (podStatus=%v) failed: %v", format.Pod(pod), podStatus, err)
 			}
 		}
 		// Create and Update pod's Cgroups

pkg/kubelet/kuberuntime/kuberuntime_container.go

@@ -658,6 +658,7 @@ func (m *kubeGenericRuntimeManager) killContainersWithSyncResult(pod *v1.Pod, ru
 			killContainerResult := kubecontainer.NewSyncResult(kubecontainer.KillContainer, container.Name)
 			if err := m.killContainer(pod, container.ID, container.Name, "", gracePeriodOverride); err != nil {
 				killContainerResult.Fail(kubecontainer.ErrKillContainer, err.Error())
+				klog.Errorf("killContainer %q(id=%q) for pod %q failed: %v", container.Name, container.ID, format.Pod(pod), err)
 			}
 			containerResults <- killContainerResult
 		}(container)