diff --git a/doc/src/sgml/ref/pg_rewind.sgml b/doc/src/sgml/ref/pg_rewind.sgml
index d98406c420..45425141fb 100644
--- a/doc/src/sgml/ref/pg_rewind.sgml
+++ b/doc/src/sgml/ref/pg_rewind.sgml
@@ -156,8 +156,10 @@ PostgreSQL documentation
        <para>
         Specifies a libpq connection string to connect to the source
         <productname>PostgreSQL</productname> server to synchronize the target with.
-        The connection must be a normal (non-replication) connection
-        with superuser access. This option requires the source
+        The connection must be a normal (non-replication) connection with a
+        superuser role or a role having sufficient permissions to execute the
+        functions used by <application>pg_rewind</application> on the source
+        server (see Notes section for details).  This option requires the source
         server to be running and not in recovery mode.
        </para>
       </listitem>
@@ -246,6 +248,30 @@ PostgreSQL documentation
  <refsect1>
   <title>Notes</title>
 
+  <para>
+   When executing <application>pg_rewind</application> using an online
+   cluster as source, a role having sufficient permissions to execute the
+   functions used by <application>pg_rewind</application> on the source
+   cluster can be used instead of a superuser.  Here is how to create such
+   a role, named <literal>rewind_user</literal> here:
+<programlisting>
+CREATE USER rewind_user LOGIN;
+GRANT EXECUTE ON function pg_catalog.pg_ls_dir(text, boolean, boolean) TO rewind_user;
+GRANT EXECUTE ON function pg_catalog.pg_stat_file(text, boolean) TO rewind_user;
+GRANT EXECUTE ON function pg_catalog.pg_read_binary_file(text) TO rewind_user;
+GRANT EXECUTE ON function pg_catalog.pg_read_binary_file(text, bigint, bigint, boolean) TO rewind_user;
+</programlisting>  
+  </para>
+
+  <para>
+   When executing <application>pg_rewind</application> using an online
+   cluster as source which has been recently promoted, it is necessary
+   to execute a <command>CHECKPOINT</command> after promotion so as its
+   control file reflects up-to-date timeline information, which is used by
+   <application>pg_rewind</application> to check if the target cluster
+   can be rewound using the designated source cluster.
+  </para>
+
   <refsect2>
    <title>How it works</title>