diff --git a/src/backend/bs_worker b/src/backend/bs_worker
index f5b7cfda645..6a11a7db025 100755
--- a/src/backend/bs_worker
+++ b/src/backend/bs_worker
@@ -2136,10 +2136,9 @@ sub getpreinstallimage {
     unlink("$dir/$ifile");
 
     # check if the image is in the cache
-    my $cacheid;
-    my $cachefile;
+    my ($cacheid, $cachefile);
     if ($cachedir) {
-      my ($cacheid, $cachefile) = get_cachefile($bestimg->{'prpa'}, $bestimg->{'hdrmd5'});
+      ($cacheid, $cachefile) = get_cachefile($bestimg->{'prpa'}, $bestimg->{'hdrmd5'});
       my $cachefilemeta = readstr("$cachefile.meta", 1) || '';
       if ($cachefilemeta eq "$bestimg->{'hdrmd5'}  :preinstallimage\n") {
 	if (link_or_copy($cachefile, "$dir/$ifile")) {