diff --git a/man5/proc.5 b/man5/proc.5
index 6fede559d..320ac2e09 100644
--- a/man5/proc.5
+++ b/man5/proc.5
@@ -2028,6 +2028,8 @@ encoded using the following two-letter codes:
     hg  - huge page advise flag
     nh  - no-huge page advise flag
     mg  - mergeable advise flag
+    um  - userfaultfd missing pages tracking (since Linux 4.3)
+    uw  - userfaultfd wprotect pages tracking (since Linux 4.3)
 .IP
 "ProtectionKey" field contains the memory protection key (see
 .BR pkeys (7))