diff --git a/block/blkdebug.c b/block/blkdebug.c
index c1cb3cb..6860a2b 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -426,7 +426,7 @@
     /* Set initial state */
     s->state = 1;
 
-    /* Open the backing file */
+    /* Open the image file */
     bs->file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options, "image",
                                bs, &child_file, false, &local_err);
     if (local_err) {