From owner-freebsd-hackers@FreeBSD.ORG Thu Jun 28 21:41:22 2012 Return-Path: Delivered-To: freebsd-hackers@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 84682106566C; Thu, 28 Jun 2012 21:41:22 +0000 (UTC) (envelope-from marcel@xcllnt.net) Received: from mail.xcllnt.net (mail.xcllnt.net [70.36.220.4]) by mx1.freebsd.org (Postfix) with ESMTP id 381D58FC0C; Thu, 28 Jun 2012 21:41:22 +0000 (UTC) Received: from sa-nc-common3-173.static.jnpr.net (natint3.juniper.net [66.129.224.36]) (authenticated bits=0) by mail.xcllnt.net (8.14.5/8.14.5) with ESMTP id q5SLf3oI037908 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Thu, 28 Jun 2012 14:41:10 -0700 (PDT) (envelope-from marcel@xcllnt.net) Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: text/plain; charset=us-ascii From: Marcel Moolenaar In-Reply-To: <20120628172526.GA1438@garage.freebsd.pl> Date: Thu, 28 Jun 2012 14:40:57 -0700 Content-Transfer-Encoding: quoted-printable Message-Id: <279E75A8-0D3C-4492-B470-BCF4A8973748@xcllnt.net> References: <4FE9B01C.30306@yandex.ru> <201206270807.23347.jhb@freebsd.org> <4FEB0079.7050008@yandex.ru> <201206271028.54477.jhb@freebsd.org> <4FEB5A3C.5050900@borderworlds.dk> <1900D4C1-E5E5-446F-ABBF-976A2DFEB36B@xcllnt.net> <4FEC22A0.9000109@freebsd.org> <4FEC2D86.2040505@freebsd.org> <8D85513D-CDFC-4D62-AA5A-F82F46E28CE5@xcllnt.net> <20120628172526.GA1438@garage.freebsd.pl> To: Pawel Jakub Dawidek X-Mailer: Apple Mail (2.1278) Cc: Doug Rabson , Marcel Moolenaar , Christian Laursen , freebsd-hackers , Andriy Gapon , Stefan Esser , "Andrey V. Elsukov" , freebsd-current Subject: Re: [CFC/CFT] large changes in the loader(8) code X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Jun 2012 21:41:22 -0000 On Jun 28, 2012, at 10:25 AM, Pawel Jakub Dawidek wrote: > On Thu, Jun 28, 2012 at 08:33:17AM -0700, Marcel Moolenaar wrote: >>=20 >> On Jun 28, 2012, at 3:10 AM, Stefan Esser wrote: >>>=20 >>> All of the above is ugly, U'm afraid :( >>=20 >> Indeed. The only sane way is to put the metadata in a partition of = its own. >> Every compliant OS will respect that and consequently will not = scribble over >> the data unintentionally. Any other scheme that puts valuable data in = some >> undocumented or unregistered location is violating the GPT spec right = away >> and is susceptible to being clobbered unintentionally. >=20 > If the user runs: >=20 > # gpart create -s GPT /dev/mirror/foo >=20 > for me it is obvious that he wants to partition the mirror device and > not individual disks. It could definitely be interpreted as the user knowing what he/she wants and as such design an infrastructure around this assumption. If users were at least as knowledgable as developers, my concerns wouldn't be as big. But we all know how knoweldgable users can be and kike it or not, even developers aren't gurus in everything. We may think to know stuff, but in practice we're just as clueless in cases as users -- more clueless even sometimes. So you may think the intend is obvious, but you should know better. > Let's modify gpart(8) to print a warning if GPT is configured on > something else than raw disk. Let's the warning say that such > configuration is non-standard and problems are expected if the disk is > shared between other OSes. Yes. I think we finally reached the point we should have reached years ago. With the proper tooling, our flexible infrastructure can be used in a safe and complaint way while still giving the freedom to those who unwisely think they know better. Build it and I'll concur. --=20 Marcel Moolenaar marcel@xcllnt.net