diff --git a/RELEASE-NOTES.md b/RELEASE-NOTES.md
index 480e4fe..a3517c1 100644
--- a/RELEASE-NOTES.md
+++ b/RELEASE-NOTES.md
@@ -1,3 +1,7 @@
+# Version 21.1.0.1
+
+**[HOTFIX]** [A "'deprecated' attribute directive ignored" warning was being thrown frequently when trying to build v21.1.0.0](https://gem5.atlassian.net/browse/GEM5-1063). While this issue did not break the build, it made reading the build output difficult and caused confused. As such a patch has been applied to fix this issue.
+
 # Version 21.1.0.0
 
 Since v21.0 we have received 780 commits with 48 unique contributors, closing 64 issues on our [Jira Issue Tracker](https://gem5.atlassian.net/).