diff --git a/src/container.c b/src/container.c
index 169eb42..63a2d11 100644
--- a/src/container.c
+++ b/src/container.c
@@ -505,6 +505,11 @@ int hyper_start_container(struct hyper_container *container,
 		goto fail;
 	}
 
+	if (hyper_watch_exec_pty(&container->exec, pod) < 0) {
+		fprintf(stderr, "faile to watch container pty\n");
+		goto fail;
+	}
+
 	stack = malloc(stacksize);
 	if (stack == NULL) {
 		perror("fail to allocate stack for container init");
@@ -518,7 +523,7 @@ int hyper_start_container(struct hyper_container *container,
 		goto fail;
 	}
 	sprintf(path, "/proc/%d/ns/mnt", pid);
-	container->exec.pid = pid;
+
 	container->ns = open(path, O_RDONLY | O_CLOEXEC);
 	if (container->ns < 0) {
 		perror("open container mount ns failed");
@@ -531,24 +536,26 @@ int hyper_start_container(struct hyper_container *container,
 		goto fail;
 	}
 
+	container->exec.pid = pid;
+	list_add_tail(&container->exec.list, &pod->exec_head);
+	container->exec.ref++;
+
 	close(arg.pipe[0]);
 	close(arg.pipe[1]);
 
-	if (hyper_watch_exec_pty(&container->exec, pod) < 0) {
-		fprintf(stderr, "faile to watch container pty\n");
-		goto fail;
-	}
-
-	fprintf(stdout, "container %s init pid is %d\n", container->id, pid);
+	fprintf(stdout, "container %s,init pid %d,ref %d\n", container->id, pid, container->exec.ref);
 	return 0;
 fail:
 	close(arg.pipe[0]);
 	close(arg.pipe[1]);
 	close(container->ns);
+	hyper_reset_event(&container->exec.e);
+	hyper_reset_event(&container->exec.errev);
 	container->ns = -1;
 	fprintf(stdout, "container %s init exit code %d\n", container->id, -1);
 	container->exec.code = -1;
 	container->exec.seq = 0;
+	container->exec.ref = 0;
 	return -1;
 }
 
@@ -624,6 +631,13 @@ void hyper_cleanup_container(struct hyper_pod *pod)
 		}
 		free(c->maps);
 		close(c->ns);
+
+		free(c->exec.id);
+		for (i = 0; i < c->exec.argc; i++) {
+			//fprintf(stdout, "argv %d %s\n", i, exec->argv[i]);
+			free(c->exec.argv[i]);
+		}
+		free(c->exec.argv);
 	}
 
 	free(pod->c);
diff --git a/src/event.c b/src/event.c
index a6ec6a7..81b6375 100644
--- a/src/event.c
+++ b/src/event.c
@@ -14,8 +14,9 @@ void hyper_reset_event(struct hyper_event *de)
 {
 	free(de->rbuf.data);
 	free(de->wbuf.data);
-
+	close(de->fd);
 	memset(de, 0, sizeof(*de));
+	de->fd = -1;
 }
 
 int hyper_init_event(struct hyper_event *de, struct hyper_event_ops *ops, void *arg)
@@ -219,8 +220,6 @@ void hyper_event_hup(struct hyper_event *de, int efd)
 {
 	if (epoll_ctl(efd, EPOLL_CTL_DEL, de->fd, NULL) < 0)
 		perror("epoll_ctl del epoll event failed");
-	close(de->fd);
-	de->fd = -1;
 	hyper_reset_event(de);
 }
 
diff --git a/src/exec.c b/src/exec.c
index 64e42a7..95826f2 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -18,13 +18,24 @@
 #include "util.h"
 #include "parse.h"
 
-static void pts_hup(struct hyper_event *de, int efd)
+static void pts_hup(struct hyper_event *de, int efd, int out)
 {
+	struct hyper_exec *exec;
 	struct hyper_pod *pod = de->ptr;
 	struct hyper_buf *buf = &ctl.tty.wbuf;
-	struct hyper_exec *exec = container_of(de, struct hyper_exec, e);
+	uint64_t seq;
 
-	fprintf(stdout, "%s\n", __func__);
+	if (out) {
+		exec = container_of(de, struct hyper_exec, e);
+		seq = exec->seq;
+	} else {
+		exec = container_of(de, struct hyper_exec, errev);
+		seq = exec->errseq;
+	}
+
+	fprintf(stdout, "%s, seq %" PRIu64"\n", __func__, seq);
+
+	hyper_event_hup(de, efd);
 
 	if (buf->get + 12 > buf->size) {
 		fprintf(stdout, "%s: tty buf full\n", __func__);
@@ -32,24 +43,27 @@ static void pts_hup(struct hyper_event *de, int efd)
 	}
 
 	/* no in event, no more data, send eof */
-	hyper_set_be64(buf->data + buf->get, exec->seq);
+	hyper_set_be64(buf->data + buf->get, seq);
 	hyper_set_be32(buf->data + buf->get + 8, 12);
 	buf->get += 12;
 
-	if (buf->get + 12 > buf->size) {
-		fprintf(stdout, "%s: tty buf full (for stderr)\n", __func__);
-	} else {
-		/* no in event, no more data, send eof in stderr */
-		hyper_set_be64(buf->data + buf->get, exec->errseq);
-		hyper_set_be32(buf->data + buf->get + 8, 12);
-		buf->get += 12;
-	}
-
 	hyper_modify_event(ctl.efd, &ctl.tty, EPOLLIN | EPOLLOUT);
 
 	hyper_release_exec(exec, pod);
 }
 
+static void stdout_hup(struct hyper_event *de, int efd)
+{
+	fprintf(stdout, "%s\n", __func__);
+	return pts_hup(de, efd, 1);
+}
+
+static void stderr_hup(struct hyper_event *de, int efd)
+{
+	fprintf(stdout, "%s\n", __func__);
+	return pts_hup(de, efd, 0);
+}
+
 static int pts_loop(struct hyper_event *de, uint64_t seq)
 {
 	int size = -1;
@@ -93,7 +107,7 @@ static int stdout_loop(struct hyper_event *de)
 
 struct hyper_event_ops pts_ops = {
 	.read		= stdout_loop,
-	.hup		= pts_hup,
+	.hup		= stdout_hup,
 	.write		= hyper_event_write,
 	.wbuf_size	= 512,
 	/* don't need read buff, the pts data will store in tty buffer */
@@ -108,8 +122,8 @@ static int stderr_loop(struct hyper_event *de)
 }
 
 struct hyper_event_ops err_ops = {
-	/* don't need to deal with hup, the hup will be dealed by pts*/
 	.read		= stderr_loop,
+	.hup		= stderr_hup,
 	/* don't need read buff, the stderr data will store in tty buffer */
 	/* don't need write buff, the stderr data is one way */
 };
@@ -173,6 +187,8 @@ int hyper_setup_exec_tty(struct hyper_exec *e)
 	e->ptyfd = open(ptmx, O_RDWR | O_NOCTTY | O_CLOEXEC);
 	fprintf(stdout, "get pty device for exec %s\n", ptmx);
 
+	fprintf(stdout, "%s pts event %p, fd %d %d\n",
+		__func__, &e->e, e->e.fd, e->ptyfd);
 	return 0;
 }
 
@@ -249,16 +265,17 @@ int hyper_watch_exec_pty(struct hyper_exec *exec, struct hyper_pod *pod)
 		fprintf(stderr, "add container pts master event failed\n");
 		return -1;
 	}
+	exec->ref++;
 
 	if (exec->errseq == 0)
 		return 0;
 
-	if (hyper_init_event(&exec->errev, &err_ops, NULL) < 0 ||
+	if (hyper_init_event(&exec->errev, &err_ops, pod) < 0 ||
 	    hyper_add_event(ctl.efd, &exec->errev, EPOLLIN) < 0) {
 		fprintf(stderr, "add container stderr event failed\n");
 		return -1;
 	}
-
+	exec->ref++;
 	return 0;
 }
 
@@ -363,6 +380,11 @@ static int hyper_do_exec_cmd(void *data)
 		goto out;
 	}
 
+	if (hyper_watch_exec_pty(exec, pod) < 0) {
+		fprintf(stderr, "add pts master event failed\n");
+		goto out;
+	}
+
 	pid = fork();
 	if (pid < 0) {
 		perror("fail to fork");
@@ -378,15 +400,10 @@ static int hyper_do_exec_cmd(void *data)
 
 		fprintf(stdout, "hyper init get ready message\n");
 		exec->pid = pid;
-		fprintf(stdout, "create exec cmd %s pid %d\n", exec->argv[0], pid);
-
+		//TODO combin ref++ and add to list.
 		list_add_tail(&exec->list, &pod->exec_head);
-
-		if (hyper_watch_exec_pty(exec, pod) < 0) {
-			fprintf(stderr, "add pts master event failed\n");
-			goto out;
-		}
-
+		exec->ref++;
+		fprintf(stdout, "create exec cmd %s pid %d,ref %d\n", exec->argv[0], pid, exec->ref);
 		ret = 0;
 		goto out;
 	}
@@ -418,12 +435,28 @@ out:
 	_exit(ret);
 }
 
+static void hyper_free_exec(struct hyper_exec *exec)
+{
+	int i;
+
+	free(exec->id);
+
+	for (i = 0; i < exec->argc; i++) {
+		//fprintf(stdout, "argv %d %s\n", i, exec->argv[i]);
+		free(exec->argv[i]);
+	}
+
+	free(exec->argv);
+	free(exec);
+}
+
 int hyper_exec_cmd(char *json, int length)
 {
 	struct hyper_exec *exec;
 	struct hyper_pod *pod = &global_pod;
 	int stacksize = getpagesize() * 4;
-	void *stack = NULL;	struct hyper_exec_arg arg = {
+	void *stack = NULL;
+	struct hyper_exec_arg arg = {
 		.pod	= pod,
 		.exec	= NULL,
 		.pipe	= {-1, -1},
@@ -442,17 +475,17 @@ int hyper_exec_cmd(char *json, int length)
 	if (exec->argv == NULL) {
 		fprintf(stderr, "cmd is %p, seq %" PRIu64 ", container %s\n",
 			exec->argv, exec->seq, exec->id);
-		goto out;
+		goto free_exec;
 	}
 
 	if (hyper_setup_exec_tty(exec) < 0) {
 		fprintf(stderr, "setup exec tty failed\n");
-		goto out;
+		goto free_exec;
 	}
 
 	if (pipe2(arg.pipe, O_CLOEXEC) < 0) {
 		perror("create pipe between pod init execcmd failed");
-		goto out;
+		goto close_tty;
 	}
 
 	arg.exec = exec;
@@ -460,7 +493,7 @@ int hyper_exec_cmd(char *json, int length)
 	stack = malloc(stacksize);
 	if (stack == NULL) {
 		perror("fail to allocate stack for container init");
-		goto out;
+		goto close_tty;
 	}
 
 	pid = clone(hyper_do_exec_cmd, stack + stacksize, CLONE_VM| CLONE_FILES| SIGCHLD, &arg);
@@ -468,12 +501,12 @@ int hyper_exec_cmd(char *json, int length)
 	free(stack);
 	if (pid < 0) {
 		perror("clone hyper_do_exec_cmd failed");
-		goto out;
+		goto close_tty;
 	}
 
 	if (hyper_get_type(arg.pipe[0], &type) < 0 || type != READY) {
 		fprintf(stderr, "hyper init doesn't get execcmd ready message\n");
-		return -1;
+		goto close_tty;
 	}
 
 	fprintf(stdout, "%s get ready message %"PRIu32 "\n", __func__, type);
@@ -481,29 +514,26 @@ int hyper_exec_cmd(char *json, int length)
 out:
 	close(arg.pipe[0]);
 	close(arg.pipe[1]);
-
 	return ret;
+close_tty:
+	close(exec->ptyfd);
+	close(exec->errfd);
+	close(exec->e.fd);
+free_exec:
+	hyper_free_exec(exec);
+	goto out;
 }
 
 int hyper_release_exec(struct hyper_exec *exec,
 		       struct hyper_pod *pod)
 {
-	int i;
-
-	if (!exec->exit && exec->seq) {
-		fprintf(stdout, "first user of exec exit\n");
-		exec->exit = 1;
-		close(exec->ptyfd);
-		exec->ptyfd = -1;
+	if (--exec->ref != 0) {
+		fprintf(stdout, "still have %d user of exec\n", exec->ref);
 		return 0;
 	}
 
 	/* exec has no pty or the pty user already exited */
 	fprintf(stdout, "last user of exec exit, release\n");
-	close(exec->e.fd);
-	close(exec->errev.fd);
-	close(exec->ptyfd);
-	close(exec->errfd);
 
 	hyper_reset_event(&exec->e);
 	hyper_reset_event(&exec->errev);
@@ -544,15 +574,7 @@ int hyper_release_exec(struct hyper_exec *exec,
 		return 0;
 	}
 
-	free(exec->id);
-
-	for (i = 0; i < exec->argc; i++) {
-		//fprintf(stdout, "argv %d %s\n", i, exec->argv[i]);
-		free(exec->argv[i]);
-	}
-
-	free(exec->argv);
-	free(exec);
+	hyper_free_exec(exec);
 
 	return 0;
 }
@@ -604,11 +626,18 @@ int hyper_send_exec_eof(int to, struct hyper_pod *pod,
 		__func__, exec->pid, exec->seq, exec->id ? exec->id : "pod");
 
 	exec->code = code;
+	exec->exit = 1;
+
+	close(exec->ptyfd);
+	exec->ptyfd = -1;
+	close(exec->errfd);
+	exec->errfd = -1;
+
 	hyper_release_exec(exec, pod);
 
 	return 0;
 }
-
+/*
 void hyper_cleanup_exec(struct hyper_pod *pod)
 {
 	struct hyper_exec *exec, *next;
@@ -618,3 +647,4 @@ void hyper_cleanup_exec(struct hyper_pod *pod)
 		hyper_release_exec(exec, pod);
 	}
 }
+*/
diff --git a/src/exec.h b/src/exec.h
index 2726e08..2da0dd8 100644
--- a/src/exec.h
+++ b/src/exec.h
@@ -20,6 +20,7 @@ struct hyper_exec {
 	int			errfd;
 	uint8_t			code;
 	uint8_t			exit;
+	uint8_t			ref;
 };
 
 struct hyper_pod;
diff --git a/src/init.c b/src/init.c
index 8af778b..58c2ecb 100644
--- a/src/init.c
+++ b/src/init.c
@@ -48,7 +48,7 @@ static int hyper_set_win_size(char *json, int length)
 	};
 	struct winsize size;
 	struct hyper_exec *exec;
-	char *name, path[128];
+	char path[128];
 	int fd, ret;
 
 	fprintf(stdout, "call hyper_win_size, json %s, len %d\n", json, length);
@@ -57,7 +57,6 @@ static int hyper_set_win_size(char *json, int length)
 		return -1;
 	}
 
-	name = ws.tty;
 	if (!ws.tty) {
 		exec = hyper_find_exec_by_seq(&global_pod, ws.seq);
 		if (exec == NULL) {
@@ -67,17 +66,18 @@ static int hyper_set_win_size(char *json, int length)
 
 		fprintf(stdout, "find exec %s, pid is %d, seq is %" PRIu64"\n",
 			exec->id ? exec->id : "pod", exec->pid, ws.seq);
-		fd = exec->ptyfd;
+		fd = dup(exec->ptyfd);
 	} else {
 		if (sprintf(path, "/dev/%s", ws.tty) < 0) {
 			fprintf(stderr, "get tty device failed\n");
 			return -1;
 		}
-		fd = hyper_open_serial_dev(name);
-		if (fd < 0) {
-			fprintf(stderr, "cannot open %s to set term size\n", name);
-			goto out;
-		}
+		fd = hyper_open_serial_dev(path);
+	}
+
+	if (fd < 0) {
+		perror("cannot open pty device to set term size");
+		goto out;
 	}
 
 	size.ws_row = ws.row;
@@ -85,7 +85,7 @@ static int hyper_set_win_size(char *json, int length)
 
 	ret = ioctl(fd, TIOCSWINSZ, &size);
 	if (ret < 0)
-		fprintf(stderr, "cannot ioctl to set %s term size\n", name);
+		perror("cannot ioctl to set pty device term size");
 
 	close(fd);
 out:
@@ -392,7 +392,6 @@ static int hyper_do_start_containers(void *data)
 
 	for (i = 0; i < pod->c_num; i++) {
 		c = &pod->c[i];
-		list_add_tail(&c->exec.list, &pod->exec_head);
 		if (hyper_start_container(c, utsns, ipcns, pod) < 0) {
 			fprintf(stderr, "fail to start container\n");
 			goto out;
@@ -403,7 +402,6 @@ static int hyper_do_start_containers(void *data)
 out:
 	if (hyper_send_type(arg->ctl_pipe[1], ret ? ERROR : READY) < 0) {
 		fprintf(stderr, "container init send ready message failed\n");
-		goto out;
 	}
 
 	close(pidns);
@@ -940,7 +938,6 @@ static void hyper_cleanup_shared(struct hyper_pod *pod)
 
 void hyper_cleanup_pod(struct hyper_pod *pod)
 {
-	hyper_cleanup_exec(pod);
 	hyper_cleanup_container(pod);
 	hyper_cleanup_network(pod);
 	hyper_cleanup_shared(pod);
@@ -1025,6 +1022,12 @@ static int hyper_ttyfd_handle(struct hyper_event *de, uint32_t len)
 
 	dprintf(stdout, "find exec %s pid %d, seq is %" PRIu64 "\n",
 		exec->id ? exec->id : "pod", exec->pid, exec->seq);
+	// if exec is exited, the event fd of exec is invalid. don't accept any input.
+	if (exec->exit) {
+		fprintf(stdout, "exec seq %" PRIu64 " exited, don't accept any input\n", exec->seq);
+		return 0;
+	}
+
 	wbuf = &exec->e.wbuf;
 
 	size = wbuf->size - wbuf->get;
diff --git a/src/net.c b/src/net.c
index bd4a58a..822d18b 100644
--- a/src/net.c
+++ b/src/net.c
@@ -707,6 +707,11 @@ static int hyper_cleanup_interface(struct rtnl_handle *rth,
 		return -1;
 	}
 
+	/* Don't down&remove lo device */
+	if (strcmp(iface->device, "lo") == 0) {
+		return 0;
+	}
+
 	if (hyper_down_nic(rth, iface->ifindex) < 0) {
 		fprintf(stderr, "up device %d failed\n", iface->ifindex);
 		return -1;
diff --git a/src/parse.c b/src/parse.c
index 98c25eb..dfb11e3 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -226,7 +226,9 @@ static int hyper_parse_container(struct hyper_pod *pod, struct hyper_container *
 	c->exec.init = 1;
 	c->exec.code = -1;
 	c->exec.e.fd = -1;
+	c->exec.errev.fd = -1;
 	c->exec.ptyfd = -1;
+	c->exec.errfd = -1;
 	c->ns = -1;
 
 	next_container = toks[i].size;
@@ -614,7 +616,9 @@ realloc:
 		goto out;
 
 	exec->ptyfd = -1;
+	exec->errfd = -1;
 	exec->e.fd = -1;
+	exec->errev.fd = -1;
 	INIT_LIST_HEAD(&exec->list);
 
 	for (i = 0, j = 0; i < n; i++) {