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<base href="https://bugs.freedesktop.org/" />
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<th>Priority</th>
<td>medium
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</tr>
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - bus-driverd racing external requests"
href="https://bugs.freedesktop.org/show_bug.cgi?id=77005">77005</a>
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<th>Assignee</th>
<td>systemd-bugs@lists.freedesktop.org
</td>
</tr>
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<th>Summary</th>
<td>bus-driverd racing external requests
</td>
</tr>
<tr>
<th>QA Contact</th>
<td>systemd-bugs@lists.freedesktop.org
</td>
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<th>Severity</th>
<td>normal
</td>
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<th>Classification</th>
<td>Unclassified
</td>
</tr>
<tr>
<th>OS</th>
<td>All
</td>
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<th>Reporter</th>
<td>dh.herrmann@gmail.com
</td>
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<th>Hardware</th>
<td>Other
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
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<th>Version</th>
<td>unspecified
</td>
</tr>
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<th>Component</th>
<td>general
</td>
</tr>
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<th>Product</th>
<td>systemd
</td>
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<p>
<div>
<pre>Ryan just made me aware of this. The following sequence works reliably with
dbus1, but not with kdbus + bus-driverd:
ADD_MATCH to=org.freedesktop.DBus
METHOD_CALL to=someone.else
If both calls are async, with dbus1, the ADD_MATCH is guaranteed to be finished
before METHOD_CALL is forwarded to someone.else. With bus-driverd, there's no
such guarantee.
I'm not really sure how to fix it. Some ideas:
* make any org.freedesktop.DBus call synchronous in the kernel (ugh, ugly!)
* support org.freedesktop.DBus only when called through bus-proxyd and make it
synchronous inside of bus-proxyd (hm, still ugly?)
* make sd-bus inspect any outgoing messages and make them synchronous if
they're targeted as org.freedesktop.DBus
* document it, but it ignore it and make people wait for ADD_MATCH to actually
finish
With "synchronous" I obviously mean just delaying any other outgoing message
until we got the response. That "waiting" can still be async.. (like HELO)
I'm actually not sure whether _any_ of the bus-driverd calls is still needed
with kdbus, but if it is, we probably need to review the other ones, too.</pre>
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