From owner-freebsd-stable@FreeBSD.ORG  Mon Sep 13 08:02:40 2010
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
Delivered-To: freebsd-stable@FreeBSD.ORG
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 487FE1065697
	for <freebsd-stable@FreeBSD.ORG>; Mon, 13 Sep 2010 08:02:40 +0000 (UTC)
	(envelope-from stb@lassitu.de)
Received: from gilb.zs64.net (gilb.zs64.net [IPv6:2001:470:1f0b:105e::1ea])
	by mx1.freebsd.org (Postfix) with ESMTP id 0F0F78FC18
	for <freebsd-stable@FreeBSD.ORG>; Mon, 13 Sep 2010 08:02:40 +0000 (UTC)
Received: by gilb.zs64.net (Postfix, from stb@lassitu.de) id D268AA0B50;
	Mon, 13 Sep 2010 08:02:38 +0000 (UTC)
Mime-Version: 1.0 (Apple Message framework v1081)
Content-Type: text/plain; charset=us-ascii
From: Stefan Bethke <stb@lassitu.de>
In-Reply-To: <201009121526.o8CFQC7T062317@lurza.secnetix.de>
Date: Mon, 13 Sep 2010 10:02:38 +0200
Content-Transfer-Encoding: quoted-printable
Message-Id: <4534A77E-FE4B-4FE2-9F90-F5F7125EF62A@lassitu.de>
References: <201009121526.o8CFQC7T062317@lurza.secnetix.de>
To: Oliver Fromme <olli@lurza.secnetix.de>
X-Mailer: Apple Mail (2.1081)
Cc: freebsd-stable@FreeBSD.ORG
Subject: Re: Serial console problems with stable/8
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Production branch of FreeBSD source code <freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>, 
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 13 Sep 2010 08:02:40 -0000


Am 12.09.2010 um 17:26 schrieb Oliver Fromme:

> I cannot even su(1) to root because it tries to print
> a message to the console, so it hangs, too.  For the same
> reason I can't use shutdown(8) either.  :-(
>=20
> This is what a hanging su(1) command looks like in ps -alxww:
>  UID   PID  PPID CPU PRI NI   VSZ   RSS MWCHAN STAT  TT       TIME =
COMMAND
>    0  1533  1532   0  76  0  3392  3180 ttydcd I+     0    0:00.05 su =
(zsh)
>=20
> Interestingly, the KDB sequences CR ~ ^B/^P/^R/ do work,
> which use the "low-level" console.  So only the "high-level"
> console is frozen.

Looking at the WCHAN, I'd speculate that it's waiting for DCD to become =
active. Are you using a proper cable with handshaking, or a three-wire =
cable?

See what stty thinks the port is set to.  It probably has clocal set, =
but shouldn't. See if you can unwedge it by setting -clocal with stty, =
then pick a proper cable or gettytab entry.


Stefan

--=20
Stefan Bethke <stb@lassitu.de>   Fon +49 151 14070811