Add check on root dir so that we can ensure its useable ahead of time

devstack/shell.py

@@ -200,6 +200,10 @@ def abspth(path):
     return os.path.abspath(path)
 
 
+def isuseable(path, options=os.W_OK|os.R_OK|os.X_OK):
+    return os.access(path, options)
+
+
 def shellquote(text):
     # TODO since there doesn't seem to be a standard lib that actually works use this way...
     do_adjust = False

stack

@@ -121,6 +121,9 @@ def run(args):
             root_dir = sh.joinpths(sh.gethomedir(), 'openstack')
     root_dir = sh.abspth(root_dir)
     setup_root(root_dir)
+    if not sh.isuseable(root_dir):
+        print(utils.color_text("Unreadable/writeable/executable root directory %r provided!" % (root_dir), "red"))
+        return False
 
     persona_fn = args.pop('persona_fn')
     if not persona_fn or not sh.isfile(persona_fn):