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<base href="https://bugs.freedesktop.org/" />
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Reading journal backwards misses entries"
href="https://bugs.freedesktop.org/show_bug.cgi?id=86855">86855</a>
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<th>Summary</th>
<td>Reading journal backwards misses entries
</td>
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<th>Product</th>
<td>systemd
</td>
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<th>Version</th>
<td>unspecified
</td>
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<th>Hardware</th>
<td>Other
</td>
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<th>OS</th>
<td>All
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>major
</td>
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<th>Priority</th>
<td>medium
</td>
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<th>Component</th>
<td>general
</td>
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<th>Assignee</th>
<td>systemd-bugs@lists.freedesktop.org
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<th>Reporter</th>
<td>jjk@jjacky.com
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<th>QA Contact</th>
<td>systemd-bugs@lists.freedesktop.org
</td>
</tr></table>
<p>
<div>
<pre>Simple illustration of the problem:
% coredumpctl list COREDUMP_PID=8212
TIME PID UID GID SIG PRESENT EXE
Sat 2014-11-29 13:17:03 CET 8212 1000 100 6 * /usr/bin/Xorg.bin
% coredumpctl list -1 COREDUMP_PID=8212
No match found.
The reason it fails to find a match with -1 is that then
sd_journal_seek_tail()/sd_journal_previous() are used, else it's be
seek_head()/next(); and apparently going backwards doen't work right.
As a test, I did a small program that uses similar matches (COREDUMP_PID=8212
AND MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1), if the loop with the call to
sd_journal_get_data() is done with SD_JOURNAL_FOREACH(j) it works, with
SD_JOURNAL_FOREACH_BACKWARDS(j) no matches are found.
Trying using another set of matches (on a COREDUMP_EXE this time), I get 13
matches going forward, only 12 going backwards.
No idea what's going on, but clearly going backwards in the journal doesn't
work properly.
This is on up-to-date Arch Linux x86_64:
% systemctl --version
systemd 217
+PAM -AUDIT -SELINUX -IMA -APPARMOR +SMACK -SYSVINIT +UTMP +LIBCRYPTSETUP
+GCRYPT +GNUTLS +ACL +XZ +LZ4 +SECCOMP +BLKID -ELFUTILS +KMOD +IDN</pre>
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</p>
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