diff --git a/builder/dockerfile/cmd_builder_commit.go b/builder/dockerfile/cmd_builder_commit.go
index da2ee4f047bc8249d955efa208b7dc509d26a025..5480a766d39c987fd7c3f6c9ced2d7dc0690ef5c 100644
--- a/builder/dockerfile/cmd_builder_commit.go
+++ b/builder/dockerfile/cmd_builder_commit.go
@@ -66,7 +66,7 @@ func (c *cmdBuilder) newContainerReference(exporting bool) (transc.Reference, er
 		return transc.Reference{}, errors.Wrapf(err, "error encoding docker-format image configuration %#v", c.stage.docker)
 	}
 
-	createdBy := strings.Join(util.CopyStrings(c.stage.docker.Config.Shell), " ")
+	createdBy := strings.Join(c.stage.docker.Config.Shell, " ")
 	if createdBy == "" {
 		createdBy = defaultShell
 	}
diff --git a/daemon/save.go b/daemon/save.go
index 708fab37db1c12cc484ae46c284aa2d2f97476a5..7206a5d4555f7860aa1a6d34594ba9952d349b2e 100644
--- a/daemon/save.go
+++ b/daemon/save.go
@@ -111,7 +111,8 @@ func (b *Backend) Save(req *pb.SaveRequest, stream pb.Control_SaveServer) (err e
 	}
 
 	if opts.sep.Enabled() {
-		return opts.sep.SeparateImage(opts.localStore, opts.oriImgList, opts.outputPath)
+		opts.logEntry.Infof("Start saving separated images %v", opts.oriImgList)
+		return opts.sep.SeparateImage(opts.localStore, opts.outputPath)
 	}
 
 	return nil
diff --git a/daemon/separator/save.go b/daemon/separator/save.go
index a455335ce663ec409b0c554573260486f85b4125..16c944608b188d7b831c1120db2840f1a9a03050 100644
--- a/daemon/separator/save.go
+++ b/daemon/separator/save.go
@@ -84,9 +84,7 @@ func GetSepSaveOptions(req *pb.SaveRequest, logEntry *logrus.Entry, dataRoot str
 }
 
 // SeparateImage the main method of Saver, tries to separated the listed images to pieces
-func (s *Saver) SeparateImage(localStore *store.Store, oriImgList []string, outputPath string) (err error) {
-	s.log.Infof("Start saving separated images %v", oriImgList)
-
+func (s *Saver) SeparateImage(localStore *store.Store, outputPath string) (err error) {
 	if err = os.MkdirAll(s.dest, constant.DefaultRootDirMode); err != nil {
 		return err
 	}