diff --git a/kernel/liveupdate/luo_session.c b/kernel/liveupdate/luo_session.c
index 5c6cebc6e326..47566db64598 100644
--- a/kernel/liveupdate/luo_session.c
+++ b/kernel/liveupdate/luo_session.c
@@ -291,10 +291,11 @@ static int luo_session_retrieve_fd(struct luo_session *session,
 	if (argp->fd < 0)
 		return argp->fd;
 
-	guard(mutex)(&session->mutex);
+	mutex_lock(&session->mutex);
 	err = luo_retrieve_file(&session->file_set, argp->token, &file);
+	mutex_unlock(&session->mutex);
 	if (err < 0)
-		goto  err_put_fd;
+		goto err_put_fd;
 
 	err = luo_ucmd_respond(ucmd, sizeof(*argp));
 	if (err)