diff --git a/qemu-nbd.c b/qemu-nbd.c
index a5c1d95..d5f8473 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -831,13 +831,13 @@
         }
         options = qemu_opts_to_qdict(opts, NULL);
         qemu_opts_reset(&file_opts);
-        blk = blk_new_open("hda", NULL, NULL, options, flags, &local_err);
+        blk = blk_new_open(NULL, NULL, options, flags, &local_err);
     } else {
         if (fmt) {
             options = qdict_new();
             qdict_put(options, "driver", qstring_from_str(fmt));
         }
-        blk = blk_new_open("hda", srcpath, NULL, options, flags, &local_err);
+        blk = blk_new_open(srcpath, NULL, options, flags, &local_err);
     }
 
     if (!blk) {