diff -u b/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php b/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
--- b/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
+++ b/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
@@ -249,8 +249,13 @@
     // In case both profile directories contain the same extension, the actual
     // profile always has precedence.
     if ($profile) {
-      $profile_handler = \Drupal::service('profile_handler');
-      $this->profileDirectories = array_merge($profile_handler->getProfileDirectories($profile), $this->profileDirectories);
+      if (\Drupal::hasService('profile_handler')) {
+        $profile_handler = \Drupal::service('profile_handler');
+        $this->profileDirectories = array_merge($profile_handler->getProfileDirectories($profile), $this->profileDirectories);
+      }
+      else {
+        $this->profileDirectories[] = drupal_get_path('profile', $profile);
+      }
     }
 
     return $this;
only in patch2:
unchanged:
--- a/core/lib/Drupal/Core/Config/ExtensionInstallStorage.php
+++ b/core/lib/Drupal/Core/Config/ExtensionInstallStorage.php
@@ -86,13 +86,13 @@ protected function getAllFolders() {
         $modules = $extensions['module'];
         // Remove the install profile as this is handled later.
         unset($modules[$install_profile]);
-        $profile_list = $listing->scan('profile');
-        if ($profile && isset($profile_list[$profile])) {
+        $profiles = $listing->scan('profile');
+        foreach ($profiles as $profile_name => $profile_object) {
           // Prime the drupal_get_filename() static cache with the profile info
           // file location so we can use drupal_get_path() on the active profile
           // during the module scan.
           // @todo Remove as part of https://www.drupal.org/node/2186491
-          drupal_get_filename('profile', $profile, $profile_list[$profile]->getPathname());
+          drupal_get_filename('profile', $profile_name, $profile_object->getPathname());
         }
         $module_list_scan = $listing->scan('module');
         $module_list = array();
@@ -121,9 +121,12 @@ protected function getAllFolders() {
           if (!isset($profile_list)) {
             $profile_list = $listing->scan('profile');
           }
-          if (isset($profile_list[$profile])) {
-            $profile_folders = $this->getComponentNames(array($profile_list[$profile]));
-            $this->folders = $profile_folders + $this->folders;
+          $profile_names = \Drupal::service('profile_handler')->getProfileDependencies($profile);
+          foreach ($profile_names as $profile_name) {
+            if (isset($profile_list[$profile_name])) {
+              $profile_folders = $this->getComponentNames(array($profile_list[$profile_name]));
+              $this->folders = $profile_folders + $this->folders;
+            }
           }
         }
       }
only in patch2:
unchanged:
--- a/core/lib/Drupal/Core/Config/InstallStorage.php
+++ b/core/lib/Drupal/Core/Config/InstallStorage.php
@@ -155,16 +155,18 @@ protected function getAllFolders() {
       // yet because the system module may not yet be enabled during install.
       // @todo Remove as part of https://www.drupal.org/node/2186491
       $listing = new ExtensionDiscovery(\Drupal::root());
-      if ($profile = drupal_get_profile()) {
-        $profile_list = $listing->scan('profile');
-        if (isset($profile_list[$profile])) {
-          // Prime the drupal_get_filename() static cache with the profile info
-          // file location so we can use drupal_get_path() on the active profile
-          // during the module scan.
-          // @todo Remove as part of https://www.drupal.org/node/2186491
-          drupal_get_filename('profile', $profile, $profile_list[$profile]->getPathname());
-          $this->folders += $this->getComponentNames(array($profile_list[$profile]));
-        }
+      $profiles = $listing->scan('profile');
+      foreach ($profiles as $profile_name => $profile_object) {
+        // Prime the drupal_get_filename() static cache with the profile info
+        // file location so we can use drupal_get_path() on the active profile
+        // during the module scan.
+        // @todo Remove as part of https://www.drupal.org/node/2186491
+        drupal_get_filename('profile', $profile_name, $profile_object->getPathname());
+      }
+      // Now that we can fetch the path, get dependent profiles and add the extensions
+      $profile_names = \Drupal::service('profile_handler')->getProfileDependencies(drupal_get_profile());
+      foreach ($profile_names as $profile_name) {
+        $this->folders += $this->getComponentNames(array($profiles[$profile_name]));
       }
       // @todo Remove as part of https://www.drupal.org/node/2186491
       $this->folders += $this->getComponentNames($listing->scan('module'));
only in patch2:
unchanged:
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -963,22 +963,31 @@ function _system_rebuild_module_data() {
   // module scan as the module scan requires knowing what the active profile is.
   // @todo Remove as part of https://www.drupal.org/node/2186491.
   $profiles = $listing->scan('profile');
-  $profile = drupal_get_profile();
-  if ($profile && isset($profiles[$profile])) {
+  foreach ($profiles as $profile_name => $profile) {
     // Prime the drupal_get_filename() static cache with the profile info file
     // location so we can use drupal_get_path() on the active profile during
     // the module scan.
     // @todo Remove as part of https://www.drupal.org/node/2186491.
-    drupal_get_filename('profile', $profile, $profiles[$profile]->getPathname());
+    drupal_get_filename('profile', $profile_name, $profile->getPathname());
   }
 
   // Find modules.
   $modules = $listing->scan('module');
-  // Include the installation profile in modules that are loaded.
+
+  $profile = drupal_get_profile();
   if ($profile) {
-    $modules[$profile] = $profiles[$profile];
+    $profile_names = \Drupal::service('profile_handler')->getProfileDependencies($profile);
+  }
+  else {
+    $profile_names = array_keys($profiles);
+  }
+  // Include the installation profile in modules that are loaded.
+  $weight = 1000;
+  foreach ($profile_names as $profile_name) {
+    $modules[$profile_name] = $profiles[$profile_name];
     // Installation profile hooks are always executed last.
-    $modules[$profile]->weight = 1000;
+    $modules[$profile_name]->weight = $weight;
+    $weight++;
   }
 
   // Set defaults for module info.
@@ -1004,7 +1013,7 @@ function _system_rebuild_module_data() {
 
     // Installation profiles are hidden by default, unless explicitly specified
     // otherwise in the .info.yml file.
-    if ($key == $profile && !isset($modules[$key]->info['hidden'])) {
+    if (in_array($key, $profile_names) && !isset($modules[$key]->info['hidden'])) {
       $modules[$key]->info['hidden'] = TRUE;
     }