diff --git a/sdk_container/src/third_party/portage-stable/metadata/layout.conf b/sdk_container/src/third_party/portage-stable/metadata/layout.conf
index 9d0db3e236..e0046e86a7 100644
--- a/sdk_container/src/third_party/portage-stable/metadata/layout.conf
+++ b/sdk_container/src/third_party/portage-stable/metadata/layout.conf
@@ -1,3 +1,4 @@
+masters = gentoo chromiumos
 use-manifests = true
 thin-manifests = true
 cache-format = md5-dict