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To: Winston Smith <smith.winston.101@gmail.com>
Subject: Re: Looking for FreeBSD u-boot/kernel debugging help (BeagleBone
 Black)
In-reply-to: Your message of "Sat, 26 Apr 2014 18:29:35 EDT."
 <CADH-AwHN0=p4z0RJZNcoRdoDJTMVAtK5F3TNCh5qdMWessQ0KQ@mail.gmail.com>
References: <CADH-AwHN0=p4z0RJZNcoRdoDJTMVAtK5F3TNCh5qdMWessQ0KQ@mail.gmail.com>
Comments: In-reply-to Winston Smith <smith.winston.101@gmail.com>
 message dated "Sat, 26 Apr 2014 18:29:35 -0400."
Date: Sat, 26 Apr 2014 16:34:38 -0700
From: Bakul Shah <bakul@bitblocks.com>
Message-Id: <20140426233438.49123B827@mail.bitblocks.com>
Cc: FreeBSD ARM <freebsd-arm@freebsd.org>
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On Sat, 26 Apr 2014 18:29:35 EDT Winston Smith <smith.winston.101@gmail.com> wrote:
>                              I also discovered that if I disconnect my
> serial terminal and reconnect it, it seems to bring the FreeBSD kernel
> to a debug prompt of sorts -- is there any documentation on this?

I suspect disconnecting/reconnecting the serial cable looks like
a break to the kernel and that drops it into the debugger "ddb".
[Though I can't seem to send a real break to it using kermit!]

Type c and hit return to continue. 

To disable this behavior I think you can do
	sysctl debug.kbd.break_to_debugger=0
or add
	debug.kbd.break_to_debugger=0
to /etc/sysctl.conf

man 1 ddb -- for debugger commands
man 4 ddb -- for kernel config options to control ddb behavior