https://jira.whamcloud.com This file is an XML representation of an issue en-us 9.4.14 940014 05-12-2023 https://jira.whamcloud.com/browse/LU-7766 Lustre <p>After <a href="http://review.whamcloud.com/16914" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/16914</a> we see the following when starting LNet:</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>[690112.179415] LNet: 8882:0:(lib-eq.c:87:LNetEQAlloc()) EQ callback is guaranteed to get every event, do you still want to set eqcount 1 for polling event which will have locking overhead? Please contact with developer to confirm </pre> </div></div> <p>Here <tt>LNetEQAlloc()</tt> is being called with a count of 0 and passing that to <tt>roundup_pow_of_two()</tt>. This is undefined behavior according to <a href="http://lxr.free-electrons.com/source/tools/include/linux/log2.h#L161" class="external-link" target="_blank" rel="nofollow noopener">http://lxr.free-electrons.com/source/tools/include/linux/log2.h#L161</a>.</p> LU-7766

LNetEQAlloc() misuses roundup_pow_of_two()

Bug Blocker Resolved Fixed Oleg Drokin John Hammond Tue, 9 Feb 2016 17:36:17 +0000 Tue, 6 Dec 2016 15:09:52 +0000 Sun, 21 Feb 2016 17:22:17 +0000 Lustre 2.8.0 0 7 <p>Oleg is planning to submit a patch for this.</p> <p>Oleg Drokin (oleg.drokin@intel.com) uploaded a new patch: <a href="http://review.whamcloud.com/18370" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/18370</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-7766" title="LNetEQAlloc() misuses roundup_pow_of_two()" class="issue-link" data-issue-key="LU-7766"><del>LU-7766</del></a> lnet: Don't call roundup_pow_of_two on zero in LNetEQAlloc<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: 1<br/> Commit: c0cd8205473d7198ca48278449dcdfb09110f2de</p> <p>I submitted the same patch upstream a few days ago, but did not notice we imported this bug into our tree too.</p> <p>just noticed the annoying new lnet warning message today. talked about it on Skype. good to know there's already a patch in flight to fix it.</p> <p>Oleg Drokin (oleg.drokin@intel.com) merged in patch <a href="http://review.whamcloud.com/18370/" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/18370/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-7766" title="LNetEQAlloc() misuses roundup_pow_of_two()" class="issue-link" data-issue-key="LU-7766"><del>LU-7766</del></a> lnet: Don't call roundup_pow_of_two on zero in LNetEQAlloc<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: <br/> Commit: e3705effd8d94be11493da754c5678de5523c877</p> <p>Landed for 2.8</p> Development Rank 1|hzy0t3: Rank (Obsolete) 9223372036854775807 Severity