[asterisk-bugs] [DAHDI-linux 0015210]: dahdi_dynamic_loc crashes as soon as a valid span pair is activated

[Asterisk Bug Tracker]

The following issue has been ASSIGNED. 
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https://issues.asterisk.org/view.php?id=15210 
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Reported By:                mapacheco
Assigned To:                sruffell
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Project:                    DAHDI-linux
Issue ID:                   15210
Category:                   dahdi_dynamic_loc
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     assigned
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Date Submitted:             2009-05-27 22:27 CDT
Last Modified:              2009-06-26 12:22 CDT
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Summary:                    dahdi_dynamic_loc crashes as soon as a valid span
pair is activated
Description: 
Sample /etc/dahdi/system.conf:
dynamic=loc,1:0,24,0
dynamic=loc,1:1,24,0
bchan=1-23
dchan=24
bchan=25-47
dchan=48
mulaw=1-23,25-47
loadzone=us
defaultzone=us

modprobe dahdi_dummy
dahdi_cfg -v

My two systems get into a hard freeze (not even Alt-SysRq works), I
already debugged and found the root of the issue, see below.

If I comment all spinlock statements on dahdi_dynamic.c function
dahdi_dynamic_receive, then it doesn't freeze. The underlying cause for the
freeze we're having a recursive spinlock request, ztd_sendmessage calls
ztdlocal_transmit which calls dahdi_dynamic_receive with dlock spinlock
held.
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 (0107028) svnbot (reporter) - 2009-06-26 12:22
 https://issues.asterisk.org/view.php?id=15210#c107028 
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Repository: dahdi
Revision: 6771

U   linux/trunk/drivers/dahdi/dahdi_dynamic.c

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r6771 | sruffell | 2009-06-26 12:22:45 -0500 (Fri, 26 Jun 2009) | 6 lines

dahdi_dynamic: Release the dlock before calling accross modules.

Resolves a hard lock due to a recursive spinlock grab at startup.

Reported by: mapacheco
(closes issue https://issues.asterisk.org/view.php?id=15210)
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http://svn.digium.com/view/dahdi?view=rev&revision=6771 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2009-06-26 12:22 svnbot         Note Added: 0107028                          
2009-06-26 12:22 svnbot         Status                   new => assigned     
2009-06-26 12:22 svnbot         Assigned To               => sruffell        
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