From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760780AbZEKWrj (ORCPT ); Mon, 11 May 2009 18:47:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760686AbZEKWrO (ORCPT ); Mon, 11 May 2009 18:47:14 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:37966 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760112AbZEKWrM (ORCPT ); Mon, 11 May 2009 18:47:12 -0400 Date: Mon, 11 May 2009 15:40:09 -0700 From: Andrew Morton To: Sukadev Bhattiprolu Cc: marc.c.dionne@gmail.com, eparis@redhat.com, eparis@parisplace.org, hch@lst.de, alan@lxorguk.ukuu.org.uk, serue@us.ibm.com, hpa@zytor.com, sukadev@us.ibm.com, linux-kernel@vger.kernel.org, jbacik@redhat.com Subject: Re: [v3][PATCH 5/5] Merge code for single andmultiple-instancemounts Message-Id: <20090511154009.a6e10a0f.akpm@linux-foundation.org> In-Reply-To: <20090511221502.GA32530@linux.vnet.ibm.com> References: <20090307180816.GA30072@us.ibm.com> <20090307181232.GF30072@us.ibm.com> <7e0fb38c0905071335g7ebe972xa82faa1161f7ff0b@mail.gmail.com> <20090507212429.GA24064@linux.vnet.ibm.com> <1241735609.2907.4.camel@dhcp231-142.rdu.redhat.com> <20090507231844.GA27609@linux.vnet.ibm.com> <20090507232110.GB27609@linux.vnet.ibm.com> <4A04F5D7.2050909@gmail.com> <20090511221502.GA32530@linux.vnet.ibm.com> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 May 2009 15:15:02 -0700 Sukadev Bhattiprolu wrote: > Marc Dionne [marc.c.dionne@gmail.com] wrote: > > On 05/07/2009 07:21 PM, Sukadev Bhattiprolu wrote: > >> Er. I meant add following lines after the memset(). > >> > >> | opts->mode = DEVPTS_DEFAULT_MODE; > >> | opts->ptmxmode = DEVPTS_DEFAULT_PTMX_MODE; > > > > Adding those two lines (with . instead of ->) does fix the issue for me, > > thanks. > > > > | > Of course we would still need to understand if/ > > | > why this patch changes the settings. > > > > That particular patch changed things because the original memcpy in > > new_pts_mount() did this: > > > > memcpy(&fsi->mount_opts, opts, sizeof(opts)); > > > > where opts was a pointer, not a structure. So only the first few bytes of > > the blank opts actually got copied over. The patch moved this memcpy to > > devpts_get_sb() and in the process fixed the sizeof error. > > Here is a cleaner fix - When user space (/etc/rc.sysinit on RHEL5) mounts > devpts, this problem might be masked since the mount system call could pass > a non-NULL 'data' parmeter to devpts_get_sb(). > > I tested this patch by directly calling the system call mount() with a NULL > data parameter. If you/Eric/Peter can confirm that this works for you, I will > send this patch to Andrew. You already sent it ;) > >From 2f7746f4df78ff57125c4714f0cd64e739ccf804 Mon Sep 17 00:00:00 2001 > From: Sukadev Bhattiprolu > Date: Mon, 11 May 2009 13:11:11 -0700 > Subject: [PATCH] devpts: Correctly set default options > > devpts_get_sb() calls memset(0) to clear mount options and calls > parse_mount_options() if user specified any mount options. The memset(0) is > bogus since the 'mode' and 'ptmxmode' options are non-zero by default. > parse_mount_options() restores options to default anyway and can properly deal > with NULL mount options. > > So in devpts_get_sb() remove memset(0) and call parse_mount_options() even for > NULL mount options. > > Bug reported by Eric Paris: http://lkml.org/lkml/2009/5/7/448. This patch fixes a post-2.6.29 regression, yes? > Signed-off-by: Sukadev Bhattiprolu (sukadev@us.ibm.com) Please use angled brackets around the email address. Some lame person's scripts probably require it. Under the he-merged-it-last rule, this patch should formally go via Al's VFS tree. But I would happily accept a stfu-and-merge it?