http://elinux.org/index.php?title=Crash_Diagnostics&feed=atom&action=history 2013-05-21T06:04:50Z Revision history for this page on the wiki MediaWiki 1.21alpha http://elinux.org/index.php?title=Crash_Diagnostics&diff=46603&oldid=prev 2011-05-09T14:29:23Z

<p>Add Category Development Tools</p> <table class='diff diff-contentalign-left'> <col class='diff-marker' /> <col class='diff-content' /> <col class='diff-marker' /> <col class='diff-content' /> <tr style='vertical-align: top;'> <td colspan='2' style="background-color: white; color:black;">← Older revision</td> <td colspan='2' style="background-color: white; color:black;">Revision as of 14:29, 9 May 2011</td> </tr><tr><td colspan="2" class="diff-lineno">Line 41:</td> <td colspan="2" class="diff-lineno">Line 41:</td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>http://www.redhatmagazine.com/2007/08/15/a-quick-overview-of-linux-kernel-crash-dump-analysis/</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>http://www.redhatmagazine.com/2007/08/15/a-quick-overview-of-linux-kernel-crash-dump-analysis/</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>http://people.redhat.com/anderson/crash_whitepaper/</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>http://people.redhat.com/anderson/crash_whitepaper/</div></td></tr> <tr><td colspan="2">&#160;</td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;">[[Category:Development Tools]]</ins></div></td></tr> <!-- diff cache key elinux:diff:version:1.11a:oldid:10975:newid:46603 --> </table>

Jsujjava http://elinux.org/index.php?title=Crash_Diagnostics&diff=10975&oldid=prev 2009-04-17T09:55:50Z

<p></p> <p><b>New page</b></p><div>kernel crash debugging technique using &quot;crash&quot; utility.<br /> <br /> == Introduction ==<br /> Most frequent issue in debugging kernel programs is lack of information; lack of information in terms of stack trace, kernel logs and crash screen-shots.<br /> Crash utility provides solution for this. It provides gdb like interface for debugging.<br /> <br /> == Prerequisites ==<br /> vmlinux object file. <br /> This is kernel image with debugging information. By default, we get compressed kernel image with no debug information.<br /> For getting, vmlinux object file, you need to install &quot;kernel-debuginfo&quot; rpm.<br /> If you want to debug any module, make sure it is compiled with gcc flag '-g'.<br /> <br /> == Installation ==<br /> We receive crash utility as rpm. <br /> rpm name is of format: crash-$version.$arch.rpm<br /> Here, $version shows version number and $arch shows system architecture.<br /> <br /> For getting crash dump:<br /> For getting crash dump, we need to add &quot;crashkernel&quot; option to grub command line.<br /> i.e. we can have:<br /> ro root=LABEL=/1 rhgb quiet crashkernel=128M@16M<br /> instead of,<br /> ro root=LABEL=/1 rhgb quiet<br /> <br /> Here, parameter &quot;crashkernel=128M@16M&quot; reserves 128MB of physical memory starting at 16MB. This reserved memory is used to preload and run the capture kernel (i.e. to capture crash dump).<br /> This command line option ensures that, whenever crash occurs, it stores crash dump at &quot;/var/crash&quot; and they are stored according to date and time.<br /> <br /> There are other options to get crash dump like diskdump, netdump, etc.<br /> <br /> Running crash Utility:<br /> 1. Debugging last kernel panic:<br /> #crash &lt;patht to vmlinux&gt; /var/crash/crash_dump_name<br /> 2. Watching current running kernel:<br /> #crash<br /> This will prompt to crash shell. Just as example, following are commands:<br /> crash&gt; help<br /> crash&gt; bt ---&gt; for backtrace<br /> crash&gt; log ---&gt; for dumping current system buffer<br /> <br /> For more information on this, you can visit at:<br /> http://www.redhatmagazine.com/2007/08/15/a-quick-overview-of-linux-kernel-crash-dump-analysis/<br /> http://people.redhat.com/anderson/crash_whitepaper/</div>

Viralmehta