From owner-freebsd-bugs@FreeBSD.ORG  Mon Dec 18 16:20:35 2006
Return-Path: <owner-freebsd-bugs@FreeBSD.ORG>
X-Original-To: freebsd-bugs@hub.freebsd.org
Delivered-To: freebsd-bugs@hub.freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [69.147.83.52])
	by hub.freebsd.org (Postfix) with ESMTP id 2642216A40F
	for <freebsd-bugs@hub.freebsd.org>;
	Mon, 18 Dec 2006 16:20:35 +0000 (UTC)
	(envelope-from gnats@FreeBSD.org)
Received: from freefall.freebsd.org (freefall.freebsd.org [69.147.83.40])
	by mx1.FreeBSD.org (Postfix) with ESMTP id CC4DB43CA3
	for <freebsd-bugs@hub.freebsd.org>;
	Mon, 18 Dec 2006 16:20:34 +0000 (GMT)
	(envelope-from gnats@FreeBSD.org)
Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1])
	by freefall.freebsd.org (8.13.4/8.13.4) with ESMTP id kBIGKLKw030374
	for <freebsd-bugs@freefall.freebsd.org>; Mon, 18 Dec 2006 16:20:21 GMT
	(envelope-from gnats@freefall.freebsd.org)
Received: (from gnats@localhost)
	by freefall.freebsd.org (8.13.4/8.13.4/Submit) id kBIGKLBn030373;
	Mon, 18 Dec 2006 16:20:21 GMT (envelope-from gnats)
Date: Mon, 18 Dec 2006 16:20:21 GMT
Message-Id: <200612181620.kBIGKLBn030373@freefall.freebsd.org>
To: freebsd-bugs@FreeBSD.org
From: Ulrich Spoerlein <uspoerlein@gmail.com>
Cc: 
Subject: Re: kern/92785: Using exported filesystem on OS/2 NFS client causes
	filesystem freeze
X-BeenThere: freebsd-bugs@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
Reply-To: Ulrich Spoerlein <uspoerlein@gmail.com>
List-Id: Bug reports <freebsd-bugs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-bugs>,
	<mailto:freebsd-bugs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-bugs>
List-Post: <mailto:freebsd-bugs@freebsd.org>
List-Help: <mailto:freebsd-bugs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-bugs>,
	<mailto:freebsd-bugs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 18 Dec 2006 16:20:35 -0000

The following reply was made to PR kern/92785; it has been noted by GNATS.

From: Ulrich Spoerlein <uspoerlein@gmail.com>
To: Konstantin Belousov <kostikbel@gmail.com>
Cc: bug-followup@freebsd.org
Subject: Re: kern/92785: Using exported filesystem on OS/2 NFS client causes filesystem freeze
Date: Mon, 18 Dec 2006 16:08:34 +0100

 Konstantin Belousov wrote:
 > Try this (not ever booted kernel with this patch applied, beware).
 > 
 > Index: ufs/ufs/ufs_lookup.c
 > ===================================================================
 > RCS file: /usr/local/arch/ncvs/src/sys/ufs/ufs/ufs_lookup.c,v
 > retrieving revision 1.82
 > diff -u -r1.82 ufs_lookup.c
 > --- ufs/ufs/ufs_lookup.c	31 Jul 2006 15:44:13 -0000	1.82
 > +++ ufs/ufs/ufs_lookup.c	15 Dec 2006 15:42:43 -0000
 > @@ -556,7 +553,10 @@
 >  	 * that point backwards in the directory structure.
 >  	 */
 >  	pdp = vdp;
 > -	if (flags & ISDOTDOT) {
 > +	if (dp->i_number == dp->i_ino) {
 > +		VREF(vdp);	/* we want ourself, ie "." */
 > +		*vpp = vdp;
 > +	} else if (flags & ISDOTDOT) {
 >  		saved_ino = dp->i_ino;
 >  		VOP_UNLOCK(pdp, 0, td);	/* race to get the inode */
 >  		error = VFS_VGET(pdp->v_mount, saved_ino,
 > @@ -565,9 +565,6 @@
 >  		if (error)
 >  			return (error);
 >  		*vpp = tdp;
 > -	} else if (dp->i_number == dp->i_ino) {
 > -		VREF(vdp);	/* we want ourself, ie "." */
 > -		*vpp = vdp;
 >  	} else {
 >  		error = VFS_VGET(pdp->v_mount, dp->i_ino,
 >  		    cnp->cn_lkflags, &tdp);
 
 
 I had a colleague of mine test this while instructing him over the phone
 and it seems to fix the problem. No deadlocks, no leaks, the OS/2
 clients can mount/ls/umount at will. All seems well.
 
 Extensive tests have NOT yet been done. I'm also a little uneasy, as the
 patch changes code that has been there since revision 1.1. I wonder how
 4.x managed these OS/2 clients. Perhaps the old nfsd/rpc code rejected
 these bogus lookups?
 
 Anyway, thank you very much for the patch, we will be running it on our
 server base shortly.
 
 Ulrich Spoerlein
 
 PS: Since this fix is UFS specific, what's with the other filesystems
 that can be NFS exported? I think I'll do some test with ext2fs or
 msdosfs exported filesystems next week.