diff --git a/sdk_container/src/third_party/coreos-overlay/sys-fs/mdadm/README.md b/sdk_container/src/third_party/coreos-overlay/sys-fs/mdadm/README.md
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+This is a fork of Gentoo's sys-fs/mdadm package. The main reason of
+having this fork is to carry two patches that are already a part of
+upstream, but the release didn't yet happen, and Gentoo does not carry
+them either.
+
+There is also a minor change to build this package by default for
+arm64 without needing an entry in accept_keywords file.