[asterisk-bugs] [Asterisk 0019025]: Conversion of hints to AO2 may changes locking order

[Asterisk Bug Tracker]

The following issue has been SUBMITTED. 
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https://issues.asterisk.org/view.php?id=19025 
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Reported By:                one47
Assigned To:                
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Project:                    Asterisk
Issue ID:                   19025
Category:                   Core/PBX
Reproducibility:            N/A
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           1.6.2.18-rc1 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2011-03-25 05:06 CDT
Last Modified:              2011-03-25 05:06 CDT
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Summary:                    Conversion of hints to AO2 may changes locking order
Description: 
Potential deadlock due to locking order change.

BEFORE the AO2 conversion, pbx.c would always grab the conlock before
grabbing the hints lock.

SINCE the conversion, the conlock is not grabbed directly at-all, and the
hints lock it the top-level lock for handling state change notifications.

Incidentally, while sending notifications, the conlock is grabbed to be
able to read the "hint" values from the dialplan. This gives an implied
locking order of hints and then conlock.

pbx.c currently says that the opposite is true.

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Issue History 
Date Modified    Username       Field                    Change               
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2011-03-25 05:06 one47          New Issue                                    
2011-03-25 05:06 one47          Asterisk Version          => 1.6.2.18-rc1    
2011-03-25 05:06 one47          Regression                => No              
2011-03-25 05:06 one47          SVN Branch (only for SVN checkouts, not tarball
releases) => N/A             
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