[asterisk-bugs] [DAHDI-linux 0017724]: [patch] Race condition in handling writes to proslic LINEFEED register

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17724 
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Reported By:                alecdavis
Assigned To:                
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Project:                    DAHDI-linux
Issue ID:                   17724
Category:                   wctdm24xxp
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
JIRA:                       DAHDI-677 
Reviewboard Link:            
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Date Submitted:             2010-07-27 06:32 CDT
Last Modified:              2010-07-29 12:58 CDT
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Summary:                    [patch] Race condition in handling writes to proslic
LINEFEED register
Description: 
set_lasttxhook_interruptible times out waiting for SLIC_LF_OPPENDING on 
fxs->lasttxhook to go.

Even changing the timeout in set_lasttxhook_interruptible to 2 Seconds,
the bottom half of <b>if (SLIC_LF_OPPENDING & fxs->lasttxhook)  {</b>
randomly get executed.




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Relationships       ID      Summary
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related to          0017318 [patch] FXS Polarity Reversal on Hangup...
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 (0125277) sruffell (administrator) - 2010-07-29 12:58
 https://issues.asterisk.org/view.php?id=17724#c125277 
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Cool.  Patch passes my tests here as well.  One thing I did notice is that
the CPU overhead for the interrupt handler increased by 1.5% (add about
1.5us to the processing time) on my debug kernel.  Probably means on a
production kernel it wouldn't be that large of a change, but could the
OPPENDING bit be checked at a slower rate than every millisecond?  But
otherwise I think the checkpatch.pl errors could be cleaned up and it
committed. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-07-29 12:58 sruffell       Note Added: 0125277                          
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