From owner-svn-src-head@FreeBSD.ORG  Thu Jan 29 18:44:08 2009
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 552191065670;
	Thu, 29 Jan 2009 18:44:08 +0000 (UTC) (envelope-from jhb@freebsd.org)
Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42])
	by mx1.freebsd.org (Postfix) with ESMTP id 248828FC1B;
	Thu, 29 Jan 2009 18:44:08 +0000 (UTC) (envelope-from jhb@freebsd.org)
Received: from server.baldwin.cx (pool-98-109-39-197.nwrknj.fios.verizon.net
	[98.109.39.197])
	by cyrus.watson.org (Postfix) with ESMTPSA id BCB9B46B52;
	Thu, 29 Jan 2009 13:44:07 -0500 (EST)
Received: from localhost (john@localhost [127.0.0.1]) (authenticated bits=0)
	by server.baldwin.cx (8.14.3/8.14.3) with ESMTP id n0TIi1ia008322;
	Thu, 29 Jan 2009 13:44:02 -0500 (EST) (envelope-from jhb@freebsd.org)
From: John Baldwin <jhb@freebsd.org>
To: Kostik Belousov <kostikbel@gmail.com>
Date: Thu, 29 Jan 2009 13:43:54 -0500
User-Agent: KMail/1.9.7
References: <200901291647.n0TGlFHZ058776@svn.freebsd.org>
	<200901291209.14313.jhb@freebsd.org>
	<20090129181523.GA2471@deviant.kiev.zoral.com.ua>
In-Reply-To: <20090129181523.GA2471@deviant.kiev.zoral.com.ua>
MIME-Version: 1.0
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200901291343.55485.jhb@freebsd.org>
X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by
	milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]);
	Thu, 29 Jan 2009 13:44:02 -0500 (EST)
X-Virus-Scanned: ClamAV 0.94.2/8919/Thu Jan 29 08:05:38 2009 on
	server.baldwin.cx
X-Virus-Status: Clean
X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 
	autolearn=ham version=3.1.3
X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx
Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org,
	src-committers@freebsd.org, Edward Tomasz Napierala <trasz@freebsd.org>
Subject: Re: svn commit: r187894 - head/sys/ufs/ffs
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: Thu, 29 Jan 2009 18:44:08 -0000

On Thursday 29 January 2009 1:15:23 pm Kostik Belousov wrote:
> On Thu, Jan 29, 2009 at 12:09:13PM -0500, John Baldwin wrote:
> > On Thursday 29 January 2009 11:47:15 am Edward Tomasz Napierala wrote:
> > > Author: trasz
> > > Date: Thu Jan 29 16:47:15 2009
> > > New Revision: 187894
> > > URL: http://svn.freebsd.org/changeset/base/187894
> > > 
> > > Log:
> > >   Make sure the cdev doesn't go away while the filesystem is still 
mounted.
> > >   Otherwise dev2udev() could return garbage.
> > >   
> > >   Reviewed by:	kib
> > >   Approved by:	rwatson (mentor)
> > >   Sponsored by:	FreeBSD Foundation
> > 
> > Is this applicable to all filesystems?  I'm curious why the VREF() on the 
> > vnode associated with the cdev entry (um_devvp) is not sufficient to 
prevent 
> > this?  I would have thought that the vnode would have held a reference on 
the 
> > cdev.
> 
> The point of this commit is that devvp vnode may be reclaimed.

So do all filesystems need this change then?

-- 
John Baldwin