diff --git a/man5/proc.5 b/man5/proc.5
index 930350442..ff7254d68 100644
--- a/man5/proc.5
+++ b/man5/proc.5
@@ -5772,6 +5772,19 @@ Any subsequent attempts to execute a command will result in
 Changing the value in this file takes effect whenever
 an application requests memory.
 .TP
+.IR /proc/sys/vm/unprivileged_userfaultfd " (since Linux 5.2)"
+.\" cefdca0a86be517bc390fc4541e3674b8e7803b0
+This (writable) file exposes a flag that controls whether
+unprivileged processes are allowed to employ
+.BR userfaultfd (2).
+If this file has the value 1, then unprivileged processes may use
+.BR userfaultfd (2).
+If this file has the value 0, then only processes that have the
+.B CAP_SYS_PTRACE
+capability may employ
+.BR userfaultfd (2).
+The default value in this file is 1.
+.TP
 .IR /proc/sysrq-trigger " (since Linux 2.4.21)"
 Writing a character to this file triggers the same SysRq function as
 typing ALT-SysRq-<character> (see the description of