From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by e33.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id l58G7nax019628 for ; Fri, 8 Jun 2007 12:07:49 -0400 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v8.3) with ESMTP id l58G7ilw192082 for ; Fri, 8 Jun 2007 10:07:47 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l58G7i6E024867 for ; Fri, 8 Jun 2007 10:07:44 -0600 Message-ID: <46697EDA.9000209@us.ibm.com> Date: Fri, 08 Jun 2007 09:07:54 -0700 From: Badari Pulavarty MIME-Version: 1.0 Subject: Re: [RFC][PATCH] /proc/pid/maps doesn't match "ipcs -m" shmid References: <787b0d920706062027s5a8fd35q752f8da5d446afc@mail.gmail.com> <20070606204432.b670a7b1.akpm@linux-foundation.org> <787b0d920706062153u7ad64179p1c4f3f663c3882f@mail.gmail.com> <20070607162004.GA27802@vino.hallyn.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: "Eric W. Biederman" Cc: "Serge E. Hallyn" , Albert Cahalan , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, torvalds@linux-foundation.org List-ID: Eric W. Biederman wrote: > >At this point given that we actually have a small user space dependency >and the fact that after I have reviewed the code it looks harmless to >change the inode number of those inodes, in both cases they are just >anonymous inodes generated with new_inode, and anything that we wrap >is likely to be equally so. > >So it looks to me like we need to do three things: >- Fix the inode number > Okay. its already done. > >- Fix the name on the hugetlbfs dentry to hold the key > I don't see need for doing this for hugetlbfs inodes. Currently, they don't base their name on "key" + basing on the "key" is kind of useless anyway (its not unique). > >- Add a big fat comment that user space programs depend on this > behavior of both the dentry name and the inode number. > I don't think, the user-space can depend on the dentry-name. It can only depend on inode# to match shmid. (since key is not unique esp. for key=0x00000000). BTW, I agree that shmid is not unique even without namespaces as its based on seq# and we wrap seq#. Thanks, Badari -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org