diff --git a/IPython/utils/submodule.py b/IPython/utils/submodule.py
index 144678c..865477d 100644
--- a/IPython/utils/submodule.py
+++ b/IPython/utils/submodule.py
@@ -87,6 +87,6 @@ def check_submodule_status(root=None):
 
 def update_submodules(repo_dir):
     """update submodules in a repo"""
-    subprocess.Popen("git submodule init", cwd=repo_dir, shell=True)
-    subprocess.Popen("git submodule update", cwd=repo_dir, shell=True)
+    subprocess.check_call("git submodule init", cwd=repo_dir, shell=True)
+    subprocess.check_call("git submodule update --recursive", cwd=repo_dir, shell=True)