Index: src/land/ArcanistGitLandEngine.php
===================================================================
--- src/land/ArcanistGitLandEngine.php
+++ src/land/ArcanistGitLandEngine.php
@@ -133,17 +133,11 @@
     // user to enter a password if they're fetching over HTTP with basic
     // authentication. See T10314.
 
-    $err = $api->execPassthru(
+    $api->execxLocal(
       'fetch --quiet -- %s %s',
       $this->getTargetRemote(),
       $this->getTargetOnto());
 
-    if ($err) {
-      throw new ArcanistUsageException(
-        pht(
-          'Fetch failed! Fix the error and run "%s" again.',
-          'arc land'));
-    }
   }
 
   private function updateWorkingCopy() {
@@ -213,18 +207,12 @@
       pht('PUSHING'),
       pht('Pushing changes to "%s".', $this->getTargetFullRef()));
 
-    $err = $api->execPassthru(
+    $api->execxLocal(
       'push -- %s %s:%s',
       $this->getTargetRemote(),
       $this->mergedRef,
       $this->getTargetOnto());
 
-    if ($err) {
-      throw new ArcanistUsageException(
-        pht(
-          'Push failed! Fix the error and run "%s" again.',
-          'arc land'));
-    }
   }
 
   private function reconcileLocalState() {