From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Ulrich Drepper" Subject: Re: [d_path 0/7] Fixes to d_path: Respin Date: Fri, 20 Apr 2007 12:17:02 -0700 Message-ID: References: <20070412090809.917795000@suse.de> <200704201721.29825.agruen@suse.de> <200704201840.07247.agruen@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Alan Cox" , jjohansen@suse.de, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org, chrisw@sous-sol.org, "Andrew Morton" To: "Andreas Gruenbacher" Return-path: In-Reply-To: <200704201840.07247.agruen@suse.de> Content-Disposition: inline Sender: linux-security-module-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On 4/20/07, Andreas Gruenbacher wrote: > The code also seems to stop at the first matching mount point. You can have > the same device mounted on the same mount point multiple times but with > different mount options, e.g., [...] You can unfortunately do many stupid things. That's the user's problem. The point is that everything works fine in an environment which does not have such bogus mounts. Namespaces are also the problem of somebody else. The people who came up with them didn't think about the ramifications. None of these problems can be reasonably and reliably fixed with more support from the kernel. > I gave a chroot example that showed that in the current > implementation, you can get pretty random clashes between mounts; there are > other cases with lazy unmounts as well. Irrelevant as well. If you create chroot problems it's your problem. The fact is that if you have a normal setup the code works fine. All other situations cannot be handled with the current kernel interface. This does not give anybody the right to say "since the code doesn't always work we can break it completely". That's completely unacceptable. If you want to improve the situation, do it. Provide a solution for the problems we are having in implementing statvfs. Then we can talk about stopping to use /proc/mounts for statvfs and you can change it in a way which would harm the old implementation. That's *my* view, but I know there will be lots of people who would even object to that. The /proc filesystem is part of the kernel API and cannot be lightly broken.