From mboxrd@z Thu Jan 1 00:00:00 1970 From: akpm@linux-foundation.org Subject: [patch for 2.6.27? 1/1] nfs: BUG_ON in nfs_follow_mountpoint Date: Tue, 02 Sep 2008 14:48:35 -0700 Message-ID: <200809022148.m82LmarS014387@imap1.linux-foundation.org> Cc: bfields@fieldses.org, linux-nfs@vger.kernel.org, akpm@linux-foundation.org, den@openvz.org, Trond.Myklebust@netapp.com To: trond.myklebust@fys.uio.no Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:52205 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752833AbYIBVth (ORCPT ); Tue, 2 Sep 2008 17:49:37 -0400 Sender: linux-nfs-owner@vger.kernel.org List-ID: From: "Denis V. Lunev" Unfortunately, BUG_ON(IS_ROOT(dentry)) can happen inside nfs_follow_mountpoint with NFS running Fedora 8 using a specific setup. See https://bugzilla.redhat.com/show_bug.cgi?id=458622 So the situation should be handled on NFS client gracefully. Signed-off-by: Denis V. Lunev Cc: Trond Myklebust Cc: J. Bruce Fields Signed-off-by: Andrew Morton --- fs/nfs/namespace.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff -puN fs/nfs/namespace.c~nfs-bug_on-in-nfs_follow_mountpoint fs/nfs/namespace.c --- a/fs/nfs/namespace.c~nfs-bug_on-in-nfs_follow_mountpoint +++ a/fs/nfs/namespace.c @@ -105,7 +105,10 @@ static void * nfs_follow_mountpoint(stru dprintk("--> nfs_follow_mountpoint()\n"); - BUG_ON(IS_ROOT(dentry)); + err = -ESTALE; + if (IS_ROOT(dentry)) + goto out_err; + dprintk("%s: enter\n", __func__); dput(nd->path.dentry); nd->path.dentry = dget(dentry); _