diff --git a/core/includes/update.inc b/core/includes/update.inc
index c628d3f..bae7961 100644
--- a/core/includes/update.inc
+++ b/core/includes/update.inc
@@ -200,54 +200,17 @@ function update_prepare_d8_bootstrap() {
     exit;
   }
 
-  // During the bootstrap to DRUPAL_BOOTSTRAP_PAGE_CACHE, code will try to read
-  // the cache but the cache tables are not compatible yet. Use the Null backend
-  // by default to avoid exceptions.
-  $settings = settings()->getAll();
-  $settings['cache']['default'] = 'cache.backend.memory';
-  new Settings($settings);
-
   // Enable UpdateServiceProvider service overrides.
   // @see update_flush_all_caches()
   $GLOBALS['conf']['container_service_providers']['UpdateServiceProvider'] = 'Drupal\Core\DependencyInjection\UpdateServiceProvider';
   $GLOBALS['conf']['update_service_provider_overrides'] = TRUE;
 
-  // Check whether settings.php needs to be rewritten.
-  $settings_exist = !empty($GLOBALS['config_directories']);
-
-  if (!$settings_exist || !is_dir(config_get_config_directory('active')) || !is_dir(config_get_config_directory('staging'))) {
-    drupal_install_config_directories();
-  }
-
-  // Bootstrap the kernel.
-  // Do not attempt to dump and write it.
-  $kernel = new DrupalKernel('update', drupal_classloader(), FALSE);
-  $kernel->boot();
-
   // module.inc is not yet loaded but there are calls to module_config_sort()
   // below.
   require_once __DIR__ . '/module.inc';
 
-  // Moves install_profile from variable to settings. You can't do that in
-  // system.install because _system_rebuild_module_data() needs the profile
-  // directly. Check that it has not been set already. This is the case for
-  // Simpletest upgrade path tests.
-  if (!settings()->get('install_profile')) {
-    $old_variable = unserialize(\Drupal::database()->query('SELECT value FROM {variable} WHERE name = :name', array(':name' => 'install_profile'))->fetchField());
-    $settings = array(
-      'settings' => array(
-        'install_profile' => (object) array(
-            'value' => $old_variable,
-            'required' => TRUE,
-        ),
-      )
-    );
-    drupal_rewrite_settings($settings);
-  }
-
   // Now remove the cache override.
   $settings = settings()->getAll();
-  unset($settings['cache']['default']);
   new Settings($settings);
   $kernel = new DrupalKernel('update', drupal_classloader(), FALSE);
   $kernel->boot();