title: "mount: Invalid argument" on Android
body: <p>I'm trying to mount an ext4 partition located on my SD card with the following: </p>
  
  <pre><code># mount -t ext4 /dev/block/mmcblk1p2 /data/sdext2
  </code></pre>
  
  <p>But it always returns "Invalid argument". I've verified that ext4 is supported through /proc/filesystems. </p>
  
  <p>Ideas on how to troubleshoot?</p>