[asterisk-bugs] [Asterisk 0011818]: Deadlock in chan_zap between zt_request and do_monitor

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=11818 
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Reported By:                michael-fig
Assigned To:                
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Project:                    Asterisk
Issue ID:                   11818
Category:                   Channels/chan_zap
Reproducibility:            random
Severity:                   major
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.16.2 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             01-22-2008 13:17 CST
Last Modified:              01-25-2008 16:50 CST
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Summary:                    Deadlock in chan_zap between zt_request and
do_monitor
Description: 
We have Asterisk installed using SIP internally and a Sangoma T1 PRI card
(AFT101) to the outside world.  Every once in a while, Asterisk would hang,
and when I investigated further, the deadlock detection code found a
deadlock in chan_zap.

I've attached the complete log (from the first Deadlock message to the
point when the connection hung) for you to look at.  In brief, there were a
lot of messages of the form:

[Jan 21 14:36:10] ERROR[4211]:
/usr/src/asterisk-1.4.16.2/include/asterisk/lock.h:338
__ast_pthread_mutex_lock: chan_zap.c line 2722 (zt_hangup): Deadlock?
waited 10 sec for mutex '&iflock'?
[Jan 21 14:36:10] ERROR[4211]:
/usr/src/asterisk-1.4.16.2/include/asterisk/lock.h:342
__ast_pthread_mutex_lock: chan_zap.c line 6804 (do_monitor): '&iflock' was
locked here.

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---------------------------------------------------------------------- 
 michael-fig - 01-25-08 16:50  
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More details: the deadlock appears to start in chan_zap (all those ringing
Dial applications in deadlock3.log are definitely not really active). 
Internal SIP calls still work, but making an outbound T1 call just hangs.

At the end of the log, I demonstrate trying to show the channels again,
but then the console refuses any further input (though still displays the
debugging and verbose output).

Is there anything else I can do to help resolve this issue? 

Issue History 
Date Modified   Username       Field                    Change               
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01-25-08 16:50  michael-fig    Note Added: 0081192                          
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