Summary:ASTERISK-26216: res_fax: Deadlock when detect fax while channel executing Playback
Reporter:Richard Mudgett (rmudgett)Labels:
Date Opened:2016-07-19 12:51:18Date Closed:2016-07-21 19:28:36
Status:Closed/CompleteComponents:Channels/chan_dahdi Channels/chan_pjsip Channels/chan_sip/General Resources/res_fax
Versions:13.9.1 Frequency of
Description:chan_dahdi, chan_pjsip, chan_sip, and FAXOPT(faxdetect) can all deadlock if the channel is executing the Playback or similar dialplan application that results in a masquerade being necessary to redirect to the fax extension when a fax is detected.  The ast_async_goto() function explicitly documents that the channel lock cannot be held when calling for this very reason.
Comments:By: David Brillert (aragon) 2016-07-19 16:10:22.202-0500

Richard are you focusing efforts on removing fax deadlocks from chan_sip?
I have an open bug report ASTERISK-24822 and was wondering if your work will help in removing the potential deadlock?

By: Richard Mudgett (rmudgett) 2016-07-19 16:39:40.086-0500

This is a different deadlock than ASTERISK-24822.  That deadlock is happening in the T.38 framehook while this happens in the CNG tone detection framehook.