From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1KEmM4-00054B-73 for mharc-grub-devel@gnu.org; Fri, 04 Jul 2008 10:33:44 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KEmM1-000545-TX for grub-devel@gnu.org; Fri, 04 Jul 2008 10:33:41 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KEmLz-00053T-1X for grub-devel@gnu.org; Fri, 04 Jul 2008 10:33:40 -0400 Received: from [199.232.76.173] (port=43103 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KEmLy-00053N-Mj for grub-devel@gnu.org; Fri, 04 Jul 2008 10:33:38 -0400 Received: from fk-out-0910.google.com ([209.85.128.189]:57622) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1KEmLy-0003ei-7L for grub-devel@gnu.org; Fri, 04 Jul 2008 10:33:38 -0400 Received: by fk-out-0910.google.com with SMTP id 18so838321fkq.10 for ; Fri, 04 Jul 2008 07:33:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:subject:from:to:in-reply-to :references:content-type:date:message-id:mime-version:x-mailer; bh=+iVqNKUhS3S7cX7hAxSOueUhKfo2o8qXM+EdMF9FolA=; b=CBmUg5CNtFkauq6EGII6beJ19Pde47iY38ve6wBz+pQkDM53eS2kje+RUtfG/kNUjW fnr9ZsH2cqWQaREdfvagEYf5YRe8wMbejweVl3ABT3S9mF+gYKPG3oY7jb3Abc15p+Jp 7/86kLN4JkPShpa4YqrzgJOZy4vMzjTLBJZ38= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:in-reply-to:references:content-type:date:message-id :mime-version:x-mailer; b=acyNSZVPplCe2BXsZbxEgyuRBNA1Md9wzKmBMeW2LHT4wMKpDwW3uzDU7ovMl/yuVk Tkhup7kq5jYsafDO8fFdOjlpJX3fXHw9eL6bmDbyGnEAu8spiOFynAzpUw3sbb1PiLaz kttRWMAEqu2ZBnVScI2GWA1kuYPwSlHwldvhs= Received: by 10.78.106.3 with SMTP id e3mr390381huc.73.1215182014624; Fri, 04 Jul 2008 07:33:34 -0700 (PDT) Received: from ?192.168.1.100? ( [213.37.137.93]) by mx.google.com with ESMTPS id p30sm216192hub.35.2008.07.04.07.33.32 (version=SSLv3 cipher=RC4-MD5); Fri, 04 Jul 2008 07:33:33 -0700 (PDT) From: Javier =?ISO-8859-1?Q?Mart=EDn?= To: The development of GRUB 2 In-Reply-To: <20080704140959.GB2663@thorin> References: <20080702142245.GA21064@thorin> <1215027160.9353.125.camel@localhost> <20080703140211.GA19341@thorin> <1215104875.8123.23.camel@localhost> <20080704000829.GE4074@thorin> <1215135163.26019.44.camel@localhost> <1215167690.26019.78.camel@localhost> <1215172834.26019.97.camel@localhost> <20080704140959.GB2663@thorin> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-K4EfTqWYaxkGmDvhRjio" Date: Fri, 04 Jul 2008 16:33:50 +0200 Message-Id: <1215182030.26019.121.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.22.2 X-detected-kernel: by monty-python.gnu.org: Linux 2.6 (newer, 2) Subject: Re: grub-probe detects ext4 wronly as ext2 X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 04 Jul 2008 14:33:42 -0000 --=-K4EfTqWYaxkGmDvhRjio Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable El vie, 04-07-2008 a las 16:09 +0200, Robert Millan escribi=C3=B3: > On Fri, Jul 04, 2008 at 02:00:34PM +0200, Javier Mart=C3=ADn wrote: > > In the nearly eight years from ext2 release to the merge of ext3 into > > the kernel, some incompatible features were introduced in ext2 proper, > > like filetype and compression. Even now, with ext4 in development and > > merged into the kernel less than five years after ext3, incompatible > > features are being backported to ext2 like the lazy inode initializing = I > > mentioned earlier. Those can hit us HARD. >=20 > So you're saying we should make our decisions based on the assumption tha= t > Linux developers could be jeopardizing our efforts by introducing incompa= tible > features by surprise, without any coordination with us, and that distribu= tors > are going to pass those features down to stable releases, knowing that th= ey > break GRUB, and again without any coordination with us? >=20 I'm not saying that they will _consciously_ try to break us, just that new flags can be introduced "just like that" and that, while ext4 is definitely making quite a fuss, the real danger is in flags like EXT2_FEATURE_INCOMPAT_META_BG, the lazy inode writing flag I mentioned to Bean, since a "best-effort" reader that ignores it can (with a very high probability) read old metadata, since if the same partition is re-formatted with ext2 the inodes will be on the same places. Thus, files from the old FS could "resurrect" (with their data in unknown state) and other nasty things. These kind of flags don't make a lot of noise in developer circles outside LKML, they are introduced without long times in "development" state and then our driver becomes "broken" in a way that will be very difficult to bugtrace. That's why I said that the bootloader should adopt a conservative stance WRT incompatible feature flags too, but the user override should be present in order to give informed users a choice without having to rebuild GRUB from source. --=-K4EfTqWYaxkGmDvhRjio Content-Type: application/pgp-signature; name=signature.asc Content-Description: Esta parte del mensaje =?ISO-8859-1?Q?est=E1?= firmada digitalmente -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iQIVAwUASG40zaSl+Fbdeo72AQKeyg//UlWobuW1Ik1N1utDY+bdwfSQdMq+Ua5F n3ebvxspK31MJuHhjsETJpVRYsfpYqcdsY+okEJOOnAY7+Jti1XDLp1mecDGDSzM anBI5lOKZKs1srIf6k2tlGnucraoQcOPU29PLaDa7FkgVYUHQfZszNVGTxF1gd8i DYP5vyRdd9apMnLwSKSOAG9Pkkt1bIdbxOSdL21lj7LxVERN1FLvd/A01pwE82SC V0t5d88hjUvMBm/X5+Hv2WtGM7xim51YvXyrX32CgRjVL8I8b/iOnAuprr2xoAsS Si74p6LPMMfpAhis0jmdViXBNnzm/U9+qxRBBVQ3JGpO7uT5LCTeWHEHWs7c9IFs jObrW5WmRlwQxbn5Ikkm8YyGeHo45DaAFhOJHbXpG8qxDI0aOmVKkk2BiqNXPVQN /ZMRA2o/wwmRQGW0BjA61W6Zi+zuL6GaKdOMjCQFo3O6ZRiEGpkN+RVd4JW3ofz5 SdGkRRtkTodL/rkoZtEgqkY5KLVEQBuuOH1phVcieE91JG4SIwCffk9ddFpp8Bar mufA/Y6YHBCpRp4hDDxmAMiPrvhfQZeh4TnGG9lyAck40Seh8ZA2czfm352GwGLn kca81GL9FMZdaCQtSIMIga2YGZuSzw76u7DmZ+ZKVtdpRR2uNdAsHtaJ/47YuqXY 777uj13dhZQ= =VX7z -----END PGP SIGNATURE----- --=-K4EfTqWYaxkGmDvhRjio--