diff --git a/core/includes/update.inc b/core/includes/update.inc
index a46f125..50b8ae5 100644
--- a/core/includes/update.inc
+++ b/core/includes/update.inc
@@ -900,8 +900,8 @@ function update_variables_to_config($config_name, array $variable_map) {
   $module = strtok($config_name, '.');
 
   // Load and set default configuration values.
-  // Throws a FileStorageReadException if there is no default configuration
-  // file, which is required to exist.
+  // Throws a StorageException if there is no default configuration file, which
+  // is required to exist.
   $file = new FileStorage(array('directory' => drupal_get_path('module', $module) . '/config'));
   $default_data = $file->read($config_name);
 
diff --git a/core/lib/Drupal/Core/Config/ConfigException.php b/core/lib/Drupal/Core/Config/ConfigException.php
index c60a449..8a81b6e 100644
--- a/core/lib/Drupal/Core/Config/ConfigException.php
+++ b/core/lib/Drupal/Core/Config/ConfigException.php
@@ -1,8 +1,15 @@
 <?php
 
+/**
+ * @file
+ * Definition of Drupal\Core\Config\ConfigException.
+ */
+
 namespace Drupal\Core\Config;
 
+use RuntimeException;
+
 /**
- * @todo
+ * A base exception to the thrown in any configuration system operations.
  */
-class ConfigException extends \Exception {}
+class ConfigException extends RuntimeException {}
diff --git a/core/lib/Drupal/Core/Config/FileStorage.php b/core/lib/Drupal/Core/Config/FileStorage.php
index 4eaadd9..09c61cc 100644
--- a/core/lib/Drupal/Core/Config/FileStorage.php
+++ b/core/lib/Drupal/Core/Config/FileStorage.php
@@ -62,12 +62,12 @@ class FileStorage implements StorageInterface {
   /**
    * Implements StorageInterface::write().
    *
-   * @throws FileStorageException
+   * @throws StorageException
    */
   public function write($name, array $data) {
     $data = $this->encode($data);
     if (!file_put_contents($this->getFilePath($name), $data)) {
-      throw new FileStorageException('Failed to write configuration file: ' . $this->getFilePath($name));
+      throw new StorageException('Failed to write configuration file: ' . $this->getFilePath($name));
     }
     return $this;
   }
@@ -75,17 +75,17 @@ class FileStorage implements StorageInterface {
   /**
    * Implements StorageInterface::read().
    *
-   * @throws FileStorageReadException
+   * @throws StorageException
    */
   public function read($name) {
     if (!$this->exists($name)) {
-      throw new FileStorageReadException("Configuration file '$name' does not exist.");
+      throw new StorageException("Configuration file '$name' does not exist.");
     }
 
     $data = file_get_contents($this->getFilePath($name));
     $data = $this->decode($data);
     if ($data === FALSE) {
-      throw new FileStorageReadException("Failed to decode configuration file '$name'.");
+      throw new StorageException("Failed to decode configuration file '$name'.");
     }
     return $data;
   }
diff --git a/core/lib/Drupal/Core/Config/FileStorageException.php b/core/lib/Drupal/Core/Config/FileStorageException.php
deleted file mode 100644
index bf3ae5f..0000000
--- a/core/lib/Drupal/Core/Config/FileStorageException.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-namespace Drupal\Core\Config;
-
-use Drupal\Core\Config\ConfigException;
-
-/**
- * @todo
- */
-class FileStorageException extends ConfigException {}
diff --git a/core/lib/Drupal/Core/Config/FileStorageReadException.php b/core/lib/Drupal/Core/Config/FileStorageReadException.php
deleted file mode 100644
index d613666..0000000
--- a/core/lib/Drupal/Core/Config/FileStorageReadException.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-namespace Drupal\Core\Config;
-
-use Drupal\Core\Config\FileStorageException;
-
-/**
- * @todo
- */
-class FileStorageReadException extends FileStorageException {}
diff --git a/core/lib/Drupal/Core/Config/StorageException.php b/core/lib/Drupal/Core/Config/StorageException.php
new file mode 100644
index 0000000..8fddd17
--- /dev/null
+++ b/core/lib/Drupal/Core/Config/StorageException.php
@@ -0,0 +1,15 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Config\StorageException.
+ */
+
+namespace Drupal\Core\Config;
+
+use Drupal\Core\Config\ConfigException;
+
+/**
+ * An exception to be thrown in case of storage controller operation errors.
+ */
+class StorageException extends ConfigException {}