From owner-freebsd-hackers@freebsd.org  Wed Nov 23 03:22:14 2016
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From: Zaphod Beeblebrox <zbeeble@gmail.com>
Date: Tue, 22 Nov 2016 22:22:11 -0500
Message-ID: <CACpH0Mcz3PkzXNEjspP=KTpOXU1TqPgKvHLDSdpSZtgKr93D6g@mail.gmail.com>
Subject: Two threads call vsyslog(), two threads in death embrace.
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I'm just agitating... but bug 214482 seems to detail that two threads
calling vsyslog() lead to a death embrace.  I'm just posting to get some
wider eyes or opinions on that.

In the bug, I've kill -QUIT the mpd5 daemon and looked at it's corpse.  I
had to kill -QUIT because the daemon is completely unresponsive.  Regular
kills don't do anything.

In the mpd5 binary, there are 3 threads.  One is sitting in poll() and the
other two are stuck asking for a lock inside the vsyslog() library function.