From owner-svn-src-head@FreeBSD.ORG  Wed Sep 26 06:42:44 2012
Return-Path: <owner-svn-src-head@FreeBSD.ORG>
Delivered-To: svn-src-head@FreeBSD.ORG
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 4B511106564A;
	Wed, 26 Sep 2012 06:42:44 +0000 (UTC) (envelope-from ache@vniz.net)
Received: from vniz.net (vniz.net [194.87.13.69])
	by mx1.freebsd.org (Postfix) with ESMTP id C698A8FC15;
	Wed, 26 Sep 2012 06:42:30 +0000 (UTC)
Received: from localhost (localhost [127.0.0.1])
	by vniz.net (8.14.5/8.14.5) with ESMTP id q8Q6Y7pF044843;
	Wed, 26 Sep 2012 10:34:08 +0400 (MSK) (envelope-from ache@vniz.net)
Received: (from ache@localhost)
	by localhost (8.14.5/8.14.5/Submit) id q8Q6Y7Cr044842;
	Wed, 26 Sep 2012 10:34:07 +0400 (MSK) (envelope-from ache)
Date: Wed, 26 Sep 2012 10:34:07 +0400
From: Andrey Chernov <ache@FreeBSD.ORG>
To: "Kenneth D. Merry" <ken@FreeBSD.ORG>
Message-ID: <20120926063407.GA44807@vniz.net>
Mail-Followup-To: Andrey Chernov <ache@freebsd.org>,
	"Kenneth D. Merry" <ken@FreeBSD.ORG>,
	Pawel Jakub Dawidek <pjd@FreeBSD.ORG>, src-committers@FreeBSD.ORG,
	svn-src-all@FreeBSD.ORG, svn-src-head@FreeBSD.ORG
References: <201209221241.q8MCfnhJ067937@svn.freebsd.org>
	<20120925233712.GA26920@nargothrond.kdm.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20120925233712.GA26920@nargothrond.kdm.org>
User-Agent: Mutt/1.5.21 (2010-09-15)
Cc: svn-src-head@FreeBSD.ORG, svn-src-all@FreeBSD.ORG,
	src-committers@FreeBSD.ORG, Pawel Jakub Dawidek <pjd@FreeBSD.ORG>
Subject: Re: svn commit: r240822 - head/sys/geom
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
	<svn-src-head.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
	<mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
	<mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 26 Sep 2012 06:42:44 -0000

On Tue, Sep 25, 2012 at 05:37:12PM -0600, Kenneth D. Merry wrote:
> >   Use the topology lock to protect list of providers while withering them.
> >   It is possible that provider is destroyed while we are iterating over the
> >   list.
> 
> This breaks devices going away in CAM.
> 
> When the da(4) driver calls disk_gone(), it is necessarily holding the SIM
> lock, which is a regular MTX_DEF mutex.  The GEOM topology lock is an sx
> lock, and of WITNESS blows up because of that:

I don't know is it related, but in recent -current I got stable panic at 
the very last stage of reboot (after buffers syncing):
reboot after panic: mutex Giant owned at ../../../geom/geom_disk.c:638
using just plain AHCI disks perhaps attached to CAM.

-- 
http://ache.vniz.net/