diff --git a/core/modules/dblog/dblog.module b/core/modules/dblog/dblog.module
index 06fef10..bebf55d 100644
--- a/core/modules/dblog/dblog.module
+++ b/core/modules/dblog/dblog.module
@@ -1,4 +1,4 @@
-<?php
+  <?php
 
 /**
  * @file
@@ -28,6 +28,12 @@ function dblog_help($route_name, RouteMatchInterface $route_match) {
       $output .= '<dd>' . t('The Database Logging module allows you to view an event log on the <a href=":dblog">Recent log messages</a> page. The log is a chronological list of recorded events containing usage data, performance data, errors, warnings and operational information. Administrators should check the log on a regular basis to ensure their site is working properly.', array(':dblog' => \Drupal::url('dblog.overview'))) . '</dd>';
       $output .= '<dt>' . t('Debugging site problems') . '</dt>';
       $output .= '<dd>' . t('In case of errors or problems with the site, the <a href=":dblog">Recent log messages</a> page can be useful for debugging, since it shows the sequence of events. The log messages include usage information, warnings, and errors.', array(':dblog' => \Drupal::url('dblog.overview'))) . '</dd>';
+      $output .= '<dt>' . t('Dblog module should not be used for forensic log as they may not work on the following scenarios -') . '</dt>';;
+      $output .= '<dd>' ;
+      $output .= '<li>' . t('It may not help to see logs if site is not accessible.') . '</li>';
+      $output .= '<li>' . t('This module writes logs to database which can slow down the website.') . '</li>';
+      $output .= '</dd>';
+      $output .= '<dt>' . t('Using syslog or similar logging mechanisms may help to overcome the above said scenarios.') . '</dt>';
       $output .= '</dl>';
       return $output;
 
diff --git a/core/modules/node/node.permissions.yml b/core/modules/node/node.permissions.yml
index f852db7..71c0345 100644
--- a/core/modules/node/node.permissions.yml
+++ b/core/modules/node/node.permissions.yml
@@ -19,12 +19,13 @@ view own unpublished content:
   title: 'View own unpublished content'
 view all revisions:
   title: 'View all revisions'
+  description: 'To view a revision, <em>you also need permission to view the content item</em> (but not to edit or delete it).'
 revert all revisions:
   title: 'Revert all revisions'
-  description: 'Role requires permission <em>view revisions</em> and <em>edit rights</em> for nodes in question or <em>administer nodes</em>.'
+  description: 'To revert a revision, <em>you also need permission to edit the content item</em> (but not to view or delete it).'
 delete all revisions:
   title: 'Delete all revisions'
-  description: 'Role requires permission to <em>view revisions</em> and <em>delete rights</em> for nodes in question or <em>administer nodes</em>.'
+  description: 'To delete a revision, <em>you also need permission to delete the content item</em> (but not to view or edit it.)'
 
 permission_callbacks:
   - \Drupal\node\NodePermissions::nodeTypePermissions
diff --git a/core/modules/node/src/NodePermissions.php b/core/modules/node/src/NodePermissions.php
index 94b2d93..532a5a6 100644
--- a/core/modules/node/src/NodePermissions.php
+++ b/core/modules/node/src/NodePermissions.php
@@ -62,14 +62,15 @@ protected function buildPermissions(NodeType $type) {
       ),
       "view $type_id revisions" => array(
         'title' => $this->t('%type_name: View revisions', $type_params),
+        'description' => t('To view a revision, <em>you also need permission to view the content item</em> (but not to edit or delete it).'),
       ),
       "revert $type_id revisions" => array(
         'title' => $this->t('%type_name: Revert revisions', $type_params),
-        'description' => t('Role requires permission <em>view revisions</em> and <em>edit rights</em> for nodes in question, or <em>administer nodes</em>.'),
+        'description' => t('To revert a revision, <em>you also need permission to edit the content item</em> (but not to view or delete it).'),
       ),
       "delete $type_id revisions" => array(
         'title' => $this->t('%type_name: Delete revisions', $type_params),
-        'description' => $this->t('Role requires permission to <em>view revisions</em> and <em>delete rights</em> for nodes in question, or <em>administer nodes</em>.'),
+        'description' => $this->t('To delete a revision, <em>you also need permission to delete the content item</em> (but not to view or edit it).'),
       ),
     );
   }