diff --git a/src/applications/differential/controller/DifferentialDiffCreateController.php b/src/applications/differential/controller/DifferentialDiffCreateController.php
index 9aaf407e28..f9d1006555 100644
--- a/src/applications/differential/controller/DifferentialDiffCreateController.php
+++ b/src/applications/differential/controller/DifferentialDiffCreateController.php
@@ -1,212 +1,218 @@
 <?php
 
 final class DifferentialDiffCreateController extends DifferentialController {
 
   public function handleRequest(AphrontRequest $request) {
     $viewer = $this->getViewer();
 
     // If we're on the "Update Diff" workflow, load the revision we're going
     // to update.
     $revision = null;
     $revision_id = $request->getURIData('revisionID');
     if ($revision_id) {
       $revision = id(new DifferentialRevisionQuery())
         ->setViewer($viewer)
         ->withIDs(array($revision_id))
         ->requireCapabilities(
           array(
             PhabricatorPolicyCapability::CAN_VIEW,
             PhabricatorPolicyCapability::CAN_EDIT,
           ))
         ->executeOne();
       if (!$revision) {
         return new Aphront404Response();
       }
     }
 
     $diff = null;
     // This object is just for policy stuff
     $diff_object = DifferentialDiff::initializeNewDiff($viewer);
-    $repository_phid = null;
+
+    if ($revision) {
+      $repository_phid = $revision->getRepositoryPHID();
+    } else {
+      $repository_phid = null;
+    }
+
     $errors = array();
     $e_diff = null;
     $e_file = null;
     $validation_exception = null;
     if ($request->isFormPost()) {
 
       $repository_tokenizer = $request->getArr(
         id(new DifferentialRepositoryField())->getFieldKey());
       if ($repository_tokenizer) {
         $repository_phid = reset($repository_tokenizer);
       }
 
       if ($request->getFileExists('diff-file')) {
         $diff = PhabricatorFile::readUploadedFileData($_FILES['diff-file']);
       } else {
         $diff = $request->getStr('diff');
       }
 
       if (!strlen($diff)) {
         $errors[] = pht(
           'You can not create an empty diff. Paste a diff or upload a '.
           'file containing a diff.');
         $e_diff = pht('Required');
         $e_file = pht('Required');
       }
 
       if (!$errors) {
         try {
           $call = new ConduitCall(
             'differential.createrawdiff',
             array(
               'diff' => $diff,
               'repositoryPHID' => $repository_phid,
               'viewPolicy' => $request->getStr('viewPolicy'),
             ));
           $call->setUser($viewer);
           $result = $call->execute();
 
           $diff_id = $result['id'];
 
           $uri = $this->getApplicationURI("diff/{$diff_id}/");
           $uri = new PhutilURI($uri);
           if ($revision) {
             $uri->replaceQueryParam('revisionID', $revision->getID());
           }
 
           return id(new AphrontRedirectResponse())->setURI($uri);
         } catch (PhabricatorApplicationTransactionValidationException $ex) {
           $validation_exception = $ex;
         }
       }
     }
 
     $form = new AphrontFormView();
     $arcanist_href = PhabricatorEnv::getDoclink('Arcanist User Guide');
     $arcanist_link = phutil_tag(
       'a',
       array(
         'href' => $arcanist_href,
         'target' => '_blank',
       ),
       pht('Learn More'));
 
     $cancel_uri = $this->getApplicationURI();
 
     $policies = id(new PhabricatorPolicyQuery())
       ->setViewer($viewer)
       ->setObject($diff_object)
       ->execute();
 
     $info_view = null;
     if (!$request->isFormPost()) {
       $info_view = id(new PHUIInfoView())
         ->setSeverity(PHUIInfoView::SEVERITY_NOTICE)
         ->setErrors(
           array(
             array(
               pht(
                 'The best way to create a diff is to use the Arcanist '.
                 'command-line tool.'),
               ' ',
               $arcanist_link,
             ),
             pht(
               'You can also paste a diff above, or upload a file '.
               'containing a diff (for example, from %s, %s or %s).',
               phutil_tag('tt', array(), 'svn diff'),
               phutil_tag('tt', array(), 'git diff'),
               phutil_tag('tt', array(), 'hg diff --git')),
           ));
     }
 
     if ($revision) {
       $title = pht('Update Diff');
       $header = pht('Update Diff');
       $button = pht('Continue');
       $header_icon = 'fa-upload';
     } else {
       $title = pht('Create Diff');
       $header = pht('Create New Diff');
       $button = pht('Create Diff');
       $header_icon = 'fa-plus-square';
     }
 
     $form
       ->setEncType('multipart/form-data')
       ->setUser($viewer);
 
     if ($revision) {
       $form->appendChild(
         id(new AphrontFormMarkupControl())
           ->setLabel(pht('Updating Revision'))
           ->setValue($viewer->renderHandle($revision->getPHID())));
     }
 
     if ($repository_phid) {
       $repository_value = array($repository_phid);
     } else {
       $repository_value = array();
     }
 
     $form
       ->appendChild(
         id(new AphrontFormTextAreaControl())
           ->setLabel(pht('Raw Diff'))
           ->setName('diff')
           ->setValue($diff)
           ->setHeight(AphrontFormTextAreaControl::HEIGHT_VERY_TALL)
           ->setError($e_diff))
       ->appendChild(
         id(new AphrontFormFileControl())
           ->setLabel(pht('Raw Diff From File'))
           ->setName('diff-file')
           ->setError($e_file))
       ->appendControl(
         id(new AphrontFormTokenizerControl())
           ->setName(id(new DifferentialRepositoryField())->getFieldKey())
           ->setLabel(pht('Repository'))
           ->setDatasource(new DiffusionRepositoryDatasource())
           ->setValue($repository_value)
           ->setLimit(1))
       ->appendChild(
         id(new AphrontFormPolicyControl())
           ->setUser($viewer)
           ->setName('viewPolicy')
           ->setPolicyObject($diff_object)
           ->setPolicies($policies)
           ->setCapability(PhabricatorPolicyCapability::CAN_VIEW))
       ->appendChild(
         id(new AphrontFormSubmitControl())
           ->addCancelButton($cancel_uri)
           ->setValue($button));
 
     $form_box = id(new PHUIObjectBoxView())
       ->setHeaderText($title)
       ->setValidationException($validation_exception)
       ->setForm($form)
       ->setBackground(PHUIObjectBoxView::WHITE_CONFIG)
       ->setFormErrors($errors);
 
     $crumbs = $this->buildApplicationCrumbs();
     if ($revision) {
       $crumbs->addTextCrumb(
         $revision->getMonogram(),
         '/'.$revision->getMonogram());
     }
     $crumbs->addTextCrumb($title);
     $crumbs->setBorder(true);
 
     $view = id(new PHUITwoColumnView())
       ->setFooter(array(
         $form_box,
         $info_view,
       ));
 
     return $this->newPage()
       ->setTitle($title)
       ->setCrumbs($crumbs)
       ->appendChild($view);
   }
 
 }