Merge "Implement namespace creation method" into stable/train

neutron/privileged/agent/linux/ip_lib.py

@@ -567,11 +567,19 @@ def create_netns(name, **kwargs):
 
     :param name: The name of the namespace to create
     """
+    pid = os.fork()
+    if pid == 0:
         try:
             netns.create(name, libc=_get_cdll())
         except OSError as e:
             if e.errno != errno.EEXIST:
-            raise
+                os._exit(1)
+        except Exception:
+            os._exit(1)
+        os._exit(0)
+    else:
+        if os.waitpid(pid, 0)[1]:
+            raise RuntimeError(_('Error creating namespace %s') % name)
 
 
 @privileged.default.entrypoint