diff --git a/src/event.c b/src/event.c
index ea38ef0..abcd30f 100644
--- a/src/event.c
+++ b/src/event.c
@@ -179,7 +179,7 @@ int hyper_handle_event(int efd, struct epoll_event *event)
 	}
 
 	if (event->events & EPOLLERR) {
-		fprintf(stderr, "get epoll err of not epool in event\n");
+		fprintf(stdout, "get epoll err on event: %p\n", he);
 		if (he->ops->hup)
 			he->ops->hup(he, efd);
 		return 0;
diff --git a/src/net.c b/src/net.c
index d255fb7..bcbe133 100644
--- a/src/net.c
+++ b/src/net.c
@@ -915,6 +915,9 @@ void hyper_cleanup_dns(struct hyper_pod *pod)
 {
 	int fd, i;
 
+	if (pod->dns == NULL)
+		return;
+
 	for (i = 0; i < pod->d_num; i++) {
 		free(pod->dns[i]);
 	}
diff --git a/src/util.c b/src/util.c
index 8f7ab24..d2af2b8 100644
--- a/src/util.c
+++ b/src/util.c
@@ -538,7 +538,6 @@ int hyper_open_channel(char *channel, int mode)
 		fd = -1;
 
 		if (strncmp(name, channel, strlen(channel))) {
-			fprintf(stderr, "channel %s, directory %s\n", channel, name);
 			continue;
 		}