title: After using rngd, [hwrng] continues to max out entropy
body: <p>I installed rngd 5 and haveged on my android, which is running Android 5.1. I made a script to test them out:</p>
  
  <p><code>#!/system/bin/sh</code></p>
  
  <p><code>haveged -w 1024 -p /dev/haveged.pid -r 0 &amp;</code></p>
  
  <p><code>rngd -d 1 -p /dev/rngd.pid -r /dev/hw_random &amp;</code></p>
  
  <p>I found that using either method to increase entropy drained battery, so I removed the scripts, binaries, and /data/system/entropy*.</p>
  
  <p>The problem I have is that this didn't stop entropy generation after rebooting several times. <code>/proc/sys/kernel/random/entropy_avail</code> is maxed out at the poolsize number, <code>/proc/sys/kernel/random/poolsize</code>. A process labeled as <code>[hwrng]</code> is running consuming far more cpu time than any other process. It's draining my battery and really slowing down the system. It seems like the hwrng process, whereever it originates, was permanently reconfigured. I found only this <code>[hwrng]</code> process searching processes for rng or haveged with <code>ps|grep</code> and <code>pgrep</code>. I didn't find any kind of hwrng file in /dev or anywhere else. I've found nothing on the search engines or rngd or haveged documentation about this. Does anybody have an idea what's going on or a way to reset the natural entropy generation of the system? I have to be missing something.</p>