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-5859 Lustre <p>See the attached reproducer script for details.</p> <p>In short, running lfs changelog after deregistering the last registered user results in an LBUG on umount of the client. While it is obviously a user error to run lfs changelog with no registered users, it shouldn't result in an LBUG.</p> Seen on master b6a3222, Robert confirmed he saw it on a master build from yesterday. LU-5859

Running lfs changelog with no registered user results in LBUG

Bug Blocker Resolved Fixed Bruno Faccini Michael MacDonald Tue, 4 Nov 2014 20:31:23 +0000 Fri, 5 Jun 2015 00:32:50 +0000 Sun, 25 Jan 2015 02:53:01 +0000 Lustre 2.7.0 Lustre 2.7.0 0 9 <p>Running the attached script results in the following:</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java">... + lctl --device LU-5859-MDT0000 changelog_deregister cl1 LU-5859-MDT0000: Deregistered changelog user <span class="code-quote">'cl1'</span> + sleep 1 + lfs changelog LU-5859-MDT0000 + kill -9 5798 + umount /tmp/LU-5859/client Message from syslogd@test1 at Nov 4 12:32:42 ... kernel:LustreError: 5800:0:(llog.c:854:llog_write()) ASSERTION( loghandle-&gt;lgh_obj != ((void *)0) ) failed: Message from syslogd@test1 at Nov 4 12:32:42 ... kernel:LustreError: 5800:0:(llog.c:854:llog_write()) LBUG </pre> </div></div> <p>Mike, can you please paste the whole stack into the bug?</p> <p>I was bisecting it to determine whether <a href="https://jira.whamcloud.com/browse/LU-1996" title="Fine-grained job activity tracking using changelogs" class="issue-link" data-issue-key="LU-1996"><del>LU-1996</del></a> was guilty or not. Seems to have been introduced by <a href="https://jira.whamcloud.com/browse/LU-5038" title="Mount hangs for hours processing some llog" class="issue-link" data-issue-key="LU-5038"><del>LU-5038</del></a> instead</p> <p>I have a stack here:<br/> crash&gt; bt<br/> PID: 3610 TASK: ffff8801fea80ae0 CPU: 5 COMMAND: "mdc_clg_send_th"<br/> #0 <span class="error">&#91;ffff88020be279f8&#93;</span> machine_kexec at ffffffff8103900b<br/> #1 <span class="error">&#91;ffff88020be27a58&#93;</span> crash_kexec at ffffffff810c62c2<br/> #2 <span class="error">&#91;ffff88020be27b28&#93;</span> panic at ffffffff8152896e<br/> #3 <span class="error">&#91;ffff88020be27ba8&#93;</span> lbug_with_loc at ffffffffa0297eeb <span class="error">&#91;libcfs&#93;</span><br/> #4 <span class="error">&#91;ffff88020be27bc8&#93;</span> llog_write at ffffffffa03d6ae4 <span class="error">&#91;obdclass&#93;</span><br/> #5 <span class="error">&#91;ffff88020be27c18&#93;</span> llog_cancel_rec at ffffffffa03d6c8f <span class="error">&#91;obdclass&#93;</span><br/> #6 <span class="error">&#91;ffff88020be27c68&#93;</span> llog_cat_cleanup at ffffffffa03db89c <span class="error">&#91;obdclass&#93;</span><br/> #7 <span class="error">&#91;ffff88020be27c98&#93;</span> llog_cat_process_cb at ffffffffa03dc7fd <span class="error">&#91;obdclass&#93;</span><br/> #8 <span class="error">&#91;ffff88020be27cf8&#93;</span> llog_process_thread at ffffffffa03d7b1f <span class="error">&#91;obdclass&#93;</span><br/> #9 <span class="error">&#91;ffff88020be27da8&#93;</span> llog_process_or_fork at ffffffffa03d9817 <span class="error">&#91;obdclass&#93;</span><br/> #10 <span class="error">&#91;ffff88020be27df8&#93;</span> llog_cat_process_or_fork at ffffffffa03dab7d <span class="error">&#91;obdclass&#93;</span><br/> #11 <span class="error">&#91;ffff88020be27e88&#93;</span> llog_cat_process at ffffffffa03dace9 <span class="error">&#91;obdclass&#93;</span><br/> #12 <span class="error">&#91;ffff88020be27ea8&#93;</span> mdc_changelog_send_thread at ffffffffa08db54b <span class="error">&#91;mdc&#93;</span><br/> #13 <span class="error">&#91;ffff88020be27ee8&#93;</span> kthread at ffffffff8109af86<br/> #14 <span class="error">&#91;ffff88020be27f48&#93;</span> kernel_thread at ffffffff8100c20a</p> <p>I'm also seeing an LBUG when unmounting the client after testing changelogs. </p> <p>I confirm that <a href="https://jira.whamcloud.com/browse/LU-5038" title="Mount hangs for hours processing some llog" class="issue-link" data-issue-key="LU-5038"><del>LU-5038</del></a> seems to be the culprit. I reverted the commit in a local build and my reproducer script no longer causes an LBUG.</p> <p>Alex, could you please offer some advice on how to fix this problem? It was apparently introduced by your patch <a href="http://review.whamcloud.com/10308" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/10308</a></p> <p>Hi. Just looking for a status update on this ticket. Seems like it should be a blocker... Any input, <a href="https://jira.whamcloud.com/secure/ViewProfile.jspa?name=bzzz" class="user-hover" rel="bzzz">bzzz</a>?</p> <p>Michael, looking at that now, thanks for reminding.</p> <p>Alex Zhuravlev (alexey.zhuravlev@intel.com) uploaded a new patch: <a href="http://review.whamcloud.com/13414" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/13414</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-5859" title="Running lfs changelog with no registered user results in LBUG" class="issue-link" data-issue-key="LU-5859"><del>LU-5859</del></a> llog: do not cleanup orphans in remote catalogs<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: 1<br/> Commit: c418baa20e78da556916f48d5dc407fa6e4aab50</p> <p>Oleg Drokin (oleg.drokin@intel.com) merged in patch <a href="http://review.whamcloud.com/13414/" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/13414/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-5859" title="Running lfs changelog with no registered user results in LBUG" class="issue-link" data-issue-key="LU-5859"><del>LU-5859</del></a> llog: do not cleanup orphans in remote catalogs<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: <br/> Commit: 97df2f4cae374130c057cbf1168ad1427c96cbc5</p> <p>Landed for 2.7</p> Duplicate LU-5877 Related LU-5038 LU-5877 Development Rank 1|hzx067: Rank (Obsolete) 16400 Severity