diff --git a/UPDATING b/UPDATING
index d03d82d9b53d..b490eb2477bb 100644
--- a/UPDATING
+++ b/UPDATING
@@ -31,6 +31,14 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 11.x IS SLOW:
 	disable the most expensive debugging functionality run
 	"ln -s 'abort:false,junk:false' /etc/malloc.conf".)
 
+20160622:
+	The the libc stub for the pipe(2) system call has been replaced with
+	a wrapper which calls the pipe2(2) system call and the pipe(2) is now
+	only implemented by the kernels which include "options
+	FREEBSD10_COMPAT" in their config file (this is the default).
+	Users should ensure that this option is enabled in their kernel
+	or upgrade userspace to r302092 before upgrading their kernel.
+
 20160527:
 	CAM will now strip leading spaces from SCSI disks' serial numbers.
 	This will effect users who create UFS filesystems on SCSI disks using