From owner-freebsd-current@FreeBSD.ORG Sat Mar 18 01:18:56 2006 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7D8BF16A41F for ; Sat, 18 Mar 2006 01:18:56 +0000 (UTC) (envelope-from dmitry@atlantis.dp.ua) Received: from postman.atlantis.dp.ua (postman.atlantis.dp.ua [193.108.47.1]) by mx1.FreeBSD.org (Postfix) with ESMTP id B3D2743D46 for ; Sat, 18 Mar 2006 01:18:55 +0000 (GMT) (envelope-from dmitry@atlantis.dp.ua) Received: from smtp.atlantis.dp.ua (smtp.atlantis.dp.ua [193.108.46.231]) by postman.atlantis.dp.ua (8.13.1/8.13.1) with ESMTP id k2I1IlK3063082; Sat, 18 Mar 2006 03:18:47 +0200 (EET) (envelope-from dmitry@atlantis.dp.ua) Date: Sat, 18 Mar 2006 03:18:47 +0200 (EET) From: Dmitry Pryanishnikov To: Dag-Erling =?iso-8859-1?Q?Sm=F8rgrav?= In-Reply-To: <86u09x2au9.fsf@xps.des.no> Message-ID: <20060318025758.U40573@atlantis.atlantis.dp.ua> References: <20060317012428.N52721@atlantis.atlantis.dp.ua> <863bhh3y05.fsf@xps.des.no> <20060317194142.C90888@atlantis.atlantis.dp.ua> <86u09x2au9.fsf@xps.des.no> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: freebsd-current@freebsd.org Subject: Re: [patch] NetBSD disklabel support for geom_bsd X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 18 Mar 2006 01:18:56 -0000 Hello! On Fri, 17 Mar 2006, Dag-Erling Sm?rgrav wrote: >> media offsets in the entries of this label are not slice-relative >> like ours, but absolute media offsets instead, and thus can point >> _outside_ NetBSD slice! Their partitions can thus be aliases for our >> slice devices. > > Yes. The offsets in our disklabels used to be device-relative too. I must admit my error regarding media offsets in FreeBSD disklabels. They actually absolute media offsets, just like in NetBSD. My patch works correctly only due to the unusially intellectual code in g_bsd_modify() which starts with the comment /* Historical braindamage... */. It understands correctly both absolute and relative offsets. Now the only valid point in step (2) of my patch is removing partition entries which point outside provider. I still think that it's too dangerous to have ad0s3e device which actually isn't part of ad0s3, but is an alias for ad0s1 instead. And I think that we can remove such alias entries regardless of partition type (not only for NetBSD slices). > It is still possible to create dangerously dedicated disks, btw, and > it is still possible to put a disklabel (or even a filesystem) > directly on a device. GEOM means *more* freedom, not less. I've never said the contrary. I'm analyzing particular case: NetBSD disklabel on sliced media. For the sliceless case, my patch will essentially be NOOP, since there will be no entry which will point outside it's provider. Sincerely, Dmitry -- Atlantis ISP, System Administrator e-mail: dmitry@atlantis.dp.ua nic-hdl: LYNX-RIPE