title: Does Linux x86 64 have both 2M and 4K page together?
body: <p>My kernel is </p>
  
  <pre><code>Linux localhost.localdomain 2.6.30 #5 SMP Tue Aug 10 00:56:36 CST 2010 x86_64 x86_64 x86_64 GNU/Linux
  </code></pre>
  
  <p>My kernel module find a 2M page while nr_hugepages is disabled.</p>
  
  <pre><code> [root@localhost ~]# cat /proc/sys/vm/nr_hugepages
  0
  
  [root@localhost ~]# cat /proc/meminfo
  ...
  Hugepagesize:       2048 kB
  DirectMap4k:        9856 kB
  DirectMap2M:     2052096 kB
  </code></pre>
  
  <p>I wonder whether linux64 kernel can have both 2M and 4K page together? And what's the condition?</p>