From owner-freebsd-questions@FreeBSD.ORG  Fri Feb 18 14:46:48 2005
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 4EE5116A4CE
	for <questions@FreeBSD.org>; Fri, 18 Feb 2005 14:46:48 +0000 (GMT)
Received: from corbulon.video-collage.com
	(static-151-204-231-237.bos.east.verizon.net [151.204.231.237])
	by mx1.FreeBSD.org (Postfix) with ESMTP id A7F6143D46
	for <questions@FreeBSD.org>; Fri, 18 Feb 2005 14:46:47 +0000 (GMT)
	(envelope-from mi@corbulon.video-collage.com)
Received: from corbulon.video-collage.com (mi@localhost.video-collage.com
	[127.0.0.1])j1IEkkla091998
	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO)
	for <questions@FreeBSD.org>; Fri, 18 Feb 2005 09:46:46 -0500 (EST)
	(envelope-from mi@corbulon.video-collage.com)
Received: (from mi@localhost)
	by corbulon.video-collage.com (8.13.1/8.13.1/Submit) id j1IEkkOW091997
	for questions@FreeBSD.org; Fri, 18 Feb 2005 09:46:46 -0500 (EST)
	(envelope-from mi)
From: Mikhail Teterin <mi@corbulon.video-collage.com>
Message-Id: <200502181446.j1IEkkOW091997@corbulon.video-collage.com>
To: questions@FreeBSD.org
Date: Fri, 18 Feb 2005 09:46:46 -0500 (EST)
X-Mailer: ELM [version 2.5 PL7]
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-Virus-Scanned: clamd / ClamAV version devel-20040615, clamav-milter version
	0.73a	on corbulon.video-collage.com
X-Virus-Status: Clean
X-Scanned-By: MIMEDefang 2.43
Subject: can not remount an FS read-only
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>,
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>,
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 18 Feb 2005 14:46:48 -0000

Hello!

My /opt filesystem (playing both LOCALBASE and X11BASE) is normally
mounted read-only (not so much for security even, as for safety).

When I add/remove ports, I remount it read-write:

	mount -orw -u /opt

do, what I need and then remount it back `ro'.

This works most of the times, but sometimes, like today (after /opt was
"open" for some time), mount responds with EBUSY:

	mount: /dev/da0s2f: Device busy

According to fstat, out of 134 files opened under /opt:

	fstat | fgrep -c /opt
	134

NONE is opened for writing:

	fstat | fgrep /opt | grep -c 'w$'
	0

Is there a bug in the open-file counter somewhere, or is fstat not
telling me the whole story? In the past, trying to force the read-only
mount (-f) caused quite a few processes to segfault (sometimes including
X-server).

Thanks!

	-mi

P.S. I've seen this on both 4- and 5-stable.