diff --git a/devstack/common_settings b/devstack/common_settings
index f66807adf9..dc426a89c5 100644
--- a/devstack/common_settings
+++ b/devstack/common_settings
@@ -39,6 +39,8 @@ if [[ "$IRONIC_BOOT_MODE" == "uefi" ]]; then
 else
     # NOTE (vsaienko) We are going to test mixed drivers/partitions in single setup.
     # Do not restrict downloading image only for specific case. Download both disk and uec images.
+    # NOTE (vdrok): Here the images are actually pre-cached by devstack, in
+    # the files folder, so they won't be downloaded again.
     add_image_link http://download.cirros-cloud.net/${CIRROS_VERSION}/cirros-${CIRROS_VERSION}-x86_64-uec.tar.gz
     add_image_link http://download.cirros-cloud.net/${CIRROS_VERSION}/cirros-${CIRROS_VERSION}-x86_64-disk.img
 fi