diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 80baa090a7..d660c06e0f 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1723,9 +1723,12 @@ void
 virDomainDiskEmptySource(virDomainDiskDefPtr def)
 {
     virStorageSourcePtr src = def->src;
+    bool readonly = src->readonly;
 
     virStorageSourceClear(src);
     src->type = VIR_STORAGE_TYPE_FILE;
+    /* readonly property is necessary for CDROMs and thus can't be cleared */
+    src->readonly = readonly;
 }