diff --git a/contrib/vhost-user-gpu/main.c b/contrib/vhost-user-gpu/main.c
index e0b6df5b4d..0ef649ffaa 100644
--- a/contrib/vhost-user-gpu/main.c
+++ b/contrib/vhost-user-gpu/main.c
@@ -1170,7 +1170,7 @@ main(int argc, char *argv[])
         fd = opt_fdnum;
     }
     if (fd == -1) {
-        g_printerr("Invalid socket");
+        g_printerr("Invalid vhost-user socket.\n");
         exit(EXIT_FAILURE);
     }
 
diff --git a/contrib/vhost-user-input/main.c b/contrib/vhost-user-input/main.c
index 8b854117f5..54f882602a 100644
--- a/contrib/vhost-user-input/main.c
+++ b/contrib/vhost-user-input/main.c
@@ -377,7 +377,7 @@ main(int argc, char *argv[])
         fd = opt_fdnum;
     }
     if (fd == -1) {
-        g_printerr("Invalid socket");
+        g_printerr("Invalid vhost-user socket.\n");
         exit(EXIT_FAILURE);
     }
     vug_init(&vi.dev, fd, vi_panic, &vuiface);