[asterisk-bugs] [JIRA] (ASTERISK-25638) Random deadlock in pjsip

[Jani Aho (JIRA)]

Jani Aho created ASTERISK-25638:
-----------------------------------

             Summary: Random deadlock in pjsip
                 Key: ASTERISK-25638
                 URL: https://issues.asterisk.org/jira/browse/ASTERISK-25638
             Project: Asterisk
          Issue Type: Bug
      Security Level: None
          Components: pjproject/pjsip
    Affects Versions: 13.6.0, 13.7.0
         Environment: Centos 7.1
Pjproject 2.4.5
            Reporter: Jani Aho
         Attachments: backtrace-threads.txt

On some of our asterisk servers which server over 50k calls per day, we experience deadlocks in pjsip. These deadlocks can occur between multiple times per day to maybe once a week.

The behaviour we see is that no SIP dialogs are created. The only messages that are sent are BYE messages, but the replies to these messages aren't handled.

After one of those occasions we enabled debugging and got backtraces of locks and threads. These are from 13.6.0, but we have had the same kinds of deadlocks on 13.7.0-rc1.

I've tried to make sense of the backtraces and I've made some observations.
1. In backtrace-threads.txt Thread 644 seems to be stuck in find_entry in pjlib/src/pj/hash.c defined on line 133. That thread has acquired the mod_ua.mutex in pjsip_ua_find_dialog

2. The threads, like thread 632, which are waiting in _lll_lock_wait are trying to acquire the mutex as above in pjsip_ua_register_dlg.

3. There are a bunch of other calls tried to be made but they don't seem to get processed by the taskprocessor.



--
This message was sent by Atlassian JIRA
(v6.2#6252)