From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Poole Subject: Re: [Ext2-devel] [RFC 0/13] extents and 48bit ext3 Date: 09 Jun 2006 14:17:55 -0400 Message-ID: <87mzcmb3cc.fsf@graviton.dyn.troilus.org> References: <4488E1A4.20305@garzik.org> <20060609083523.GQ5964@schatzie.adilger.int> <44898EE3.6080903@garzik.org> <448992EB.5070405@garzik.org> <20060609174146.GO1651@parisc-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linus Torvalds , Alex Tomas , Jeff Garzik , Andrew Morton , ext2-devel , linux-kernel@vger.kernel.org, cmm@us.ibm.com, linux-fsdevel@vger.kernel.org, Andreas Dilger Return-path: Received: from 24-75-174-210-st.chvlva.adelphia.net ([24.75.174.210]:24718 "EHLO sanosuke.troilus.org") by vger.kernel.org with ESMTP id S1750806AbWFISR4 (ORCPT ); Fri, 9 Jun 2006 14:17:56 -0400 To: Matthew Wilcox In-Reply-To: <20060609174146.GO1651@parisc-linux.org> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Matthew Wilcox writes: > On Fri, Jun 09, 2006 at 10:30:06AM -0700, Linus Torvalds wrote: > > And I'm not saying that just because it's a filesystem, and people get > > upset if they lose data. No, I'm saying it because from a maintenance > > standpoint, such a filesystem has almost zero cost. > > One of the costs (and I'm not disagreeing with your main point; > I think forking ext3 to ext4 at this point is reasonable), is that > bugfixes applied to one don't necessarily get applied to the other. > I found some recently between ext2 and ext3, and submitted those, but I > only audited one file. There's lots more to look at and I just haven't > found the time recently. Going to three variations is a lot more work > for auditing, and it might be worth splitting some bits which genuinely > are the same into common code. If you want more details on this kind of issue, look at CP-Miner. A paper published earlier this year in IEEE TSE[1] reports that that tool found 421 cut-and-paste-related possible bugs in Linux, of which 49 were real bugs, 249 were false positives, and 123 could not be proven either true or false positives. [1]- http://doi.ieeecomputersociety.org/10.1109/TSE.2006.28 Michael Poole