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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> kernelnewbies-bounces@kernelnewbies.org [mailto:kernelnewbies-bounces@kernelnewbies.org]
<b>On Behalf Of </b>Kenneth Adam Miller<br>
<b>Sent:</b> Thursday, October 22, 2015 12:14 PM<br>
<b>To:</b> Kernelnewbies<br>
<b>Subject:</b> Query Hard Memory Addresses<o:p></o:p></span></p>
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<p class="MsoNormal">So, previously it was discussed that /dev/mem could be used to mmap a specific hardware memory into a process. Now I need to unit test some userland code that does exactly that, but I need to make sure that the unit test selects a small
page that is always free in kernel land. How can I query mem to just grab the location of a free page?<o:p></o:p></p>
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<p class="MsoNormal">(my development setup is different from my other deployment; in deployment these values are hard coded, in development they occur on a qemu emulator)<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I suppose it might work to write a kernel module that allocates a page in its init routine and then provides the address to user space via a /proc entry.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Jeff Haran<o:p></o:p></span></p>
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