diff --git a/trustzone-awared-vm/Host/vtzb_proxy/serial_port.c b/trustzone-awared-vm/Host/vtzb_proxy/serial_port.c
index dc25b039d3c29e553528226706f8d8d9ee4a5716..6e7ff8ca1dda08f3bbea2ebe426bc7e177f8f355 100644
--- a/trustzone-awared-vm/Host/vtzb_proxy/serial_port.c
+++ b/trustzone-awared-vm/Host/vtzb_proxy/serial_port.c
@@ -169,6 +169,8 @@ static void do_check_stat_serial_port()
                     tlogd("vm %d started, connect fd %d, create read thread\n", i, serial_port->sock);
                     serial_port->opened = true;
                     serial_port->offset = 0;
+                    g_pollfd[i].fd = serial_port->sock;
+                    g_serial_array[i] = serial_port;
                     create_reader_thread(serial_port, i);
                 }
             }
@@ -176,6 +178,9 @@ static void do_check_stat_serial_port()
             ret = access(serial_port->path, R_OK | W_OK);
             if (ret) {
                 tlogd("vm %d closed, fd %d is invalid, should close\n", i, serial_port->sock);
+                g_pollfd[i].fd = -1;
+                serial_port->opened = false;
+                g_serial_array[i] = NULL;
                 release_vm_file(serial_port, i);
             }
         }
diff --git a/trustzone-awared-vm/Host/vtzb_proxy/thread_pool.c b/trustzone-awared-vm/Host/vtzb_proxy/thread_pool.c
index e897e78c289777a8639086bfde8b9d2cb6f117d0..69cefd0e0cf7bf9b032e9dbce794aba0b9818b42 100644
--- a/trustzone-awared-vm/Host/vtzb_proxy/thread_pool.c
+++ b/trustzone-awared-vm/Host/vtzb_proxy/thread_pool.c
@@ -222,6 +222,11 @@ static void *deal_packet_thread(void *arg)
             continue;
         }
         buf_len = ret + serial_port->offset;
+        /*
+         * while loop will deal all complete packets, left the incomplete one in the
+         * starting position of rd_buf, so the offset should be 0 echo read times
+         */
+        offset = 0;
         while (1) {
             void *packet = NULL;
             packet = get_packet_item(serial_port->rd_buf, buf_len, &offset);
@@ -238,7 +243,12 @@ static void *deal_packet_thread(void *arg)
     }
 
 end:
-    tlogd("reader thread %d exit\n", serial_port->index);
+    if (serial_port) {
+        serial_port->opened = false;
+        tlogi("reader thread %d exited\n", serial_port->index);
+    } else {
+        tloge("serial_port is null, and reader thread exit\n");
+    }
     return NULL;
 }
 
diff --git a/trustzone-awared-vm/Host/vtzb_proxy/vtzb_proxy.c b/trustzone-awared-vm/Host/vtzb_proxy/vtzb_proxy.c
index 62fa837579b27386af08ec30c0ba49faa1802b9b..2388dbfcfdcbc9f07f7fbcf516779bb1b1efa0d8 100644
--- a/trustzone-awared-vm/Host/vtzb_proxy/vtzb_proxy.c
+++ b/trustzone-awared-vm/Host/vtzb_proxy/vtzb_proxy.c
@@ -775,6 +775,8 @@ END:
 }
 
 int main() {
+    int ret = 0;
+
     serial_port_list_init();
     if (thread_pool_init(&g_pool))
         goto END2;
@@ -783,6 +785,18 @@ int main() {
 
     while (1) {
         check_stat_serial_port();
+        ret = safepoll(g_pollfd, SERIAL_PORT_NUM, 20*1000);
+        if (ret <= 0) {
+            continue;
+        }
+        for (int i = 0; i < SERIAL_PORT_NUM; i++) {
+            // when vm restart quickly, use poll can capture this event
+            if (g_pollfd[i].revents & POLLHUP) {
+                tlogi("vm %d got POLLHUP event, release vm\n", i);
+                release_vm_file(g_serial_array[i], i);
+            }
+        }
+
     }
 
 END1: