diff --git a/base/mutex.h b/base/mutex.h
index 59594ae883..f0c13b8adc 100644
--- a/base/mutex.h
+++ b/base/mutex.h
@@ -129,7 +129,9 @@ public:
     ResetEvent(event_); // necessary?
     // mtx.lock();
 #else
+    pthread_mutex_lock(&mtx.native_handle());
     pthread_cond_wait(&event_, &mtx.native_handle());
+    pthread_mutex_unlock(&mtx.native_handle());
 #endif
   }
 
@@ -139,4 +141,4 @@ private:
 #else
   pthread_cond_t event_;
 #endif
-};
\ No newline at end of file
+};