diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 39a0ee29b42d52914dfd3685a5c8f7ba27bcdb16..b862f727b73d3da6958c5be1eea92d6374e9bedc 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -18550,10 +18550,12 @@ qemuDomainBlockCopyCommon(virDomainObjPtr vm,
                      * new image must refer to it in the metadata */
                     mirrorBacking = disk->src->backingStore;
                 }
+            } else {
+                mirrorBacking = mirror->backingStore;
             }
 
             if (!(crdata = qemuBuildStorageSourceChainAttachPrepareBlockdevTop(mirror,
-                                                                               mirror->backingStore,
+                                                                               mirrorBacking,
                                                                                priv->qemuCaps)))
                 goto endjob;
         }