From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Lindgren <john.lindgren@tds.net>
Subject: snd_pcm_drop causing lockup with DMix
Date: Sun, 28 Feb 2010 10:37:21 -0500
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Hi,

A couple of weeks ago I reported a rather serious bug #4914 that can
cause a multi-threaded using ALSA to lock up so that it can only be
ended with SIGKILL.

I maintain the ALSA output part of Audacious, and I need to be able to
play audio in one thread of the program and then signal that thread to
stop from another.  The way to do this in ALSA, if I understand
correctly, is to interrupt the thread that is sending audio with a call
to snd_pcm_drop.  But using DMix makes the first thread hang up in a
snd_pcm_wait call with a timeout of -1.

Is anyone working on this bug?  Is there any more help I can provide?

John Lindgren