title: can't restart adb as root on android
body: <p>I know that by typing <code>adb root</code> I can restart my adb service on Android phone as root. But when I type it it just hangs forever saying that it's restarting the service:</p>
  
  <pre><code>$ adb root
  restarting adbd as root
  </code></pre>
  
  <p>What could be wrong here? How to debug?</p>
  
  <p>Then if quit it and run <code>adb shell</code> it also hangs. I then can <code>adb shell</code> into it only after I reboot my phone.</p>