<ul>
<?php

 $args= array(
  'posts_per_page' => -1
);
  query_posts($args);
if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
    <li>

         <?php
    $args = array(
      'posts_per_page' => -1,
        'meta_key' => 'user_submit_name',
     'meta_value' => get_the_author(),
     'meta_compare' => '='
    );
    $myquery = new WP_Query($args);

    echo '<h2>Found: ' . $myquery->found_posts . '</h2> by ' . get_the_author() . '</h2><br>';

    while ( $myquery->have_posts() ) {
        $myquery->the_post();
        echo '<li><a href="' . get_permalink() . '">' . get_the_title() . '</a></li>';
    }
?>

     <?php   wp_reset_postdata(); ?>

    </li>

<?php endwhile; ?> <?php endif; ?>
</ul>