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LKML: Coiby Xu: Re: [PATCH v7 2/7] crash_dump: make dm crypt keys persist for the kdump kernel
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User space can interact with<br />><br />> an encrypted disk volume.<br />><br />>> +/sys/kernel/config/crash_dm_crypt_keys for setup,<br />>> +<br />>> +1. Tell the 1st kernel what keys are needed to unlock the disk volumes,<br />><br />> first<br />><br />>> + # Add key #1<br />>> + mkdir /sys/kernel/config/crash_dm_crypt_keys/7d26b7b4-e342-4d2d-b660-7426b0996720<br />>> + # Add key #1's description<br />>> + echo cryptsetup:7d26b7b4-e342-4d2d-b660-7426b0996720 > /sys/kernel/config/crash_dm_crypt_keys/description<br />>> +<br />>> + # how many keys do we have now?<br />>> + cat /sys/kernel/config/crash_dm_crypt_keys/count<br />>> + 1<br />>> +<br />>> + # Add key#2 in the same way<br />><br />> key #2<br />>(be consisent)<br />><br />>> +<br />>> + # how many keys do we have now?<br />>> + cat /sys/kernel/config/crash_dm_crypt_keys/count<br />>> + 2<br />>> +<br />>> +2. Load the dump-capture kernel<br />>> +<br />>> +3. After dump-capture kerne get booted, restore the keys to user keyring<br />><br />> After the dump-capture kernel is booted,<br /><br />Thanks for catching the above issues! I'll apply all your suggested<br />changes to next version.<br /><br />><br />>> + echo yes > /sys/kernel/crash_dm_crypt_keys/restore<br />>> +<br />>> Contact<br />>> =======<br />>><br />><br />>-- <br />>~Randy<br />><br />><br /><br />-- <br />Best regards,<br />Coiby<br /><br /><br /></pre></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerr.gif" width="32" height="32" alt="\" /></td></tr><tr><td align="right" valign="bottom"> 聽 </td></tr><tr><td align="right" valign="bottom">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerl.gif" width="32" height="32" alt="\" /></td><td class="c">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerr.gif" width="32" height="32" alt="/" /></td></tr><tr><td align="right" valign="top" colspan="2"> 聽 </td><td class="lm">Last update: 2025-01-16 08:37 聽聽 [from the cache]<br />漏2003-2020 <a href="http://blog.jasper.es/"><span itemprop="editor">Jasper Spaans</span></a>|hosted at <a href="https://www.digitalocean.com/?refcode=9a8e99d24cf9">Digital Ocean</a> and my Meterkast|<a href="http://blog.jasper.es/categories.html#lkml-ref">Read the blog</a></td><td>聽</td></tr></table><script language="javascript" src="/js/styleswitcher.js" type="text/javascript"></script></body></html>