title: After git revert, merge showing no changes and already updated
body: <p>I have a <code>dev</code> branch which already merged with branches <code>featureA</code> and <code>featureB</code>.
  I merged that <code>dev</code> branch to <code>master</code> and pushed to remote. Later I identified <code>featureB</code> is not yet ready to merge with <code>master</code> as there is a faulty commit. So I revert that merge of  <code>dev</code> --> <code>master</code>. </p>
  
  <pre><code>git revert -m 1 &lt;merge-commit-hash&gt;
  </code></pre>
  
  <p>Then I am trying to merge <code>featureA</code> to <code>master</code>. But I cannot merge. It will say <code>Already up to date</code>.</p>
  
  <p>I know the reason as Linus Torvalds said,</p>
  
  <blockquote>
    <p>Linus explains the situation:</p>
    
    <p>Reverting a regular commit just effectively undoes what that commit
        did, and is fairly straightforward. But reverting a merge commit also
        undoes the <em>data</em> that the commit changed, but it does absolutely
        nothing to the effects on <em>history</em> that the merge had.</p>
    
    <p>So the merge will still exist, and it will still be seen as joining
        the two branches together, and future merges will see that merge as
        the last shared state - and the revert that reverted the merge brought
        in will not affect that at all.</p>
    
    <p>So a "revert" undoes the data changes, but it's very much <em>not</em> an
        "undo" in the sense that it doesn't undo the effects of a commit on
        the repository history.</p>
    
    <p>So if you think of "revert" as "undo", then you're going to always
        miss this part of reverts. Yes, it undoes the data, but no, it doesn't
        undo history.</p>
  </blockquote>
  
  <p>In this situation only solution to merge that <code>dev</code> again to <code>master</code> is <code>revert the revert commit</code>. But I only want to merge the one branch included in <code>dev</code> branch, that is <code>featureA</code></p>
  
  <p>How can I merge the branch (<code>featureA</code>) to mainline branch (<code>master</code>), that included in reverted merge branch (<code>dev</code>)  ?</p>