diff --git a/UPDATING b/UPDATING
index f79948d828fd..291c23038ff4 100644
--- a/UPDATING
+++ b/UPDATING
@@ -51,6 +51,14 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 12.x IS SLOW:
 
 ****************************** SPECIAL WARNING: ******************************
 
+20170523:
+	The "ino64" 64-bit inode project has been committed, which extends
+	a number of types to 64 bits.  In order to upgrade, carefully follow
+	the full procedure documented below under the heading "To rebuild
+	everything and install it on the current system."  Specifically, a
+	reboot is required after installing the new kernel before installing
+	world.
+
 20170424:
 	The NATM framework including the en(4), fatm(4), hatm(4), and
 	patm(4) devices has been removed.  Consumers should plan a