write_unlock(&em_tree->lock);
        if (ret) {
                test_err("case4 [0x%llx 0x%llx): ret %d",
-                        start, len, ret);
+                        start, start + len, ret);
                goto out;
        }
        if (em && (start < em->start || start + len > extent_map_end(em))) {
                test_err(
 "case4 [0x%llx 0x%llx): ret %d, added wrong em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx)",
-                        start, len, ret, em->start, em->len, em->block_start,
+                        start, start + len, ret, em->start, em->len, em->block_start,
                         em->block_len);
                ret = -EINVAL;
        }