diff --git a/util/libreboot-utils/lib/io.c b/util/libreboot-utils/lib/io.c
index 0bab9ee5..de5f8c76 100644
--- a/util/libreboot-utils/lib/io.c
+++ b/util/libreboot-utils/lib/io.c
@@ -456,6 +456,8 @@ gbe_mv(void)
 	if (errno != EXDEV)
 		goto ret_gbe_mv;
 
+	err(errno, "TODO: cross-filesystem atomic writes currently broken");
+
 	/*
 	 * cross-filesystem: copy into target dir tmp
 	 */