+ /* If we lack the permissions to configure the
+ * loopback device, but we find it to be already
+ * configured, let's exit cleanly, in order to
+ * supported unprivileged containers. */
+ if (r == -EPERM && check_loopback(rtnl))
+ return 0;
+
+ return log_warning_errno(r, "Failed to configure loopback device: %m");
+ }