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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/1127/">https://reviewboard.asterisk.org/r/1127/</a>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Could you be a little more explicit in what channel is being "potentially" locked here? The code, as it exists today, explicitly unlocks the SIP channel and the pvt before engaging in the use of the MASTER_CHANNEL() construct, keeping merely a reference to the channel.
If the problem is within the MASTER_CHANNEL function, shouldn't this change fix that function as well?</pre>
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<p>- Tilghman</p>
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<p>On February 25th, 2011, 1:40 p.m., Brett Bryant wrote:</p>
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<div>Review request for Asterisk Developers.</div>
<div>By Brett Bryant.</div>
<p style="color: grey;"><i>Updated 2011-02-25 13:40:19</i></p>
<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Use of MASTER_CHANNEL in chan_sip causes pbx_setvar_helper to potentially lock a channel before iterating through the channel container to find the master channel. This violates locking order, and when two threads are doing this at the same time they can both end up in a deadlock holding the channel locks that the others are trying to acquire through the iterator.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Tested functionality of code and accuracy before and after change which removed the use of the MASTER_CHANNEL function.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>/tags/1.8.3-rc2/channels/chan_sip.c <span style="color: grey">(308543)</span></li>
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<p><a href="https://reviewboard.asterisk.org/r/1127/diff/" style="margin-left: 3em;">View Diff</a></p>
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