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-14494 Lustre <p>In <tt>mdt_close_handle_layouts()</tt> the client supplied FID may not identify an existing object. So we should check before calling <tt>lu_object_attr()</tt>.</p> LU-14494

check object existence in mdt_close_handle_layouts()

Bug Minor Resolved Fixed John Hammond John Hammond Fri, 5 Mar 2021 18:45:43 +0000 Wed, 28 Apr 2021 13:45:15 +0000 Tue, 30 Mar 2021 16:26:29 +0000 Lustre 2.15.0 0 5 <p><a href="https://review.whamcloud.com/#/c/41905/" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/#/c/41905/</a></p> <p>EX-14494 mdt: check object exists in mdt_close_handle_layouts()</p> <p>In mdt_close_handle_layouts() the client supplied FID may not identify<br/> an existing object. So check for this before calling lu_object_attr().</p> <p>Signed-off-by: John L. Hammond &lt;jhammond@whamcloud.com&gt;<br/> Change-Id: Ib1710ca4bf7587e0496b3a37a2afb65f81250455</p> <p>Oleg Drokin (green@whamcloud.com) merged in patch <a href="https://review.whamcloud.com/41905/" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/41905/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-14494" title="check object existence in mdt_close_handle_layouts()" class="issue-link" data-issue-key="LU-14494"><del>LU-14494</del></a> mdt: check object exists in mdt_close_handle_layouts()<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: <br/> Commit: 075bea805efe8a7ef1a3aabd8dd2c166bb52115b</p> <p>Landed for 2.15</p> <p>Alex,<br/> I think John has raised this issue elsewhere (though I can't find it), so I will do it again here - should we remove this <tt>LASSERT(LOHA_EXISTS)</tt> and just return <tt>&#45;ENOENT</tt> in this case? Jira is littered with tickets where the <tt>LOHA_EXISTS</tt> assertion is triggered (41 different tickets at last count, I just hit another one in LFSCK over the weekend), and in many cases the solution is just to add extra code to check that the object does not exist <em>before</em> calling <tt>lu&#95;object&#95;attr&#45;&gt;lu&#95;object&#95;exists()</tt>, which isn't really simplifying the code, and causes customer outages. I think this LASSERT has outlived its usefulness if we are adding lines of code just to avoid triggering the LASSERT.</p> <p><a href="https://jira.whamcloud.com/browse/LU-14493" title="return only existing objects from mdt_object_find()" class="issue-link" data-issue-key="LU-14493">LU-14493</a></p> <p>Andreas, I'm not really a defender of that LASSERT(), I didn't introduce that at least <img class="emoticon" src="https://jira.whamcloud.com/images/icons/emoticons/smile.png" height="16" width="16" align="absmiddle" alt="" border="0"/> but I see some logic for that assertion - there is no point to ask for attributes on non-existing object (which has no attributes by definition). OK, say we change lu_object_attr() to return -ENOENT, but then we have to check/fix &gt;60 callers as normally they do like:</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java"> <span class="code-keyword">if</span> (S_ISDIR(mdd_object_type(obj))) </pre> </div></div> <p>would that be really different from checking all the places to add if (*_object_exists())... ?<br/> I think at some point John suggested to have a wrapper that checks for existance internally and use that everywhere except few places when we can expect non-existing object as a valid case?</p> <p><a href="https://jira.whamcloud.com/browse/LU-14493" title="return only existing objects from mdt_object_find()" class="issue-link" data-issue-key="LU-14493">LU-14493</a></p> Duplicate Related LU-14493 Development Rank 1|i01oon: Rank (Obsolete) 9223372036854775807 Severity