diff --git a/qemu-char.c b/qemu-char.c
index 2e50a10..cbd6b9a 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -94,6 +94,7 @@
 CharDriverState *qemu_chr_alloc(void)
 {
     CharDriverState *chr = g_malloc0(sizeof(CharDriverState));
+    qemu_mutex_init(&chr->chr_write_lock);
     return chr;
 }
 
@@ -132,7 +133,7 @@
 int qemu_chr_fe_write_all(CharDriverState *s, const uint8_t *buf, int len)
 {
     int offset = 0;
-    int res;
+    int res = 0;
 
     qemu_mutex_lock(&s->chr_write_lock);
     while (offset < len) {