diff --git a/blockdev.c b/blockdev.c
index 7c83baa353ca11e10af5d6b241aec219d94ff11d..e5d450f0bb9ac199c4524b66752d60a17994dde6 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -527,6 +527,8 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
                      if_name[type], mediastr, unit_id);
     }
     dinfo->bdrv = bdrv_new(dinfo->id);
+    dinfo->bdrv->open_flags = snapshot ? BDRV_O_SNAPSHOT : 0;
+    dinfo->bdrv->read_only = ro;
     dinfo->devaddr = devaddr;
     dinfo->type = type;
     dinfo->bus = bus_id;