Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762738Ab3DCRUt (ORCPT ); Wed, 3 Apr 2013 13:20:49 -0400 Received: from db3ehsobe002.messaging.microsoft.com ([213.199.154.140]:40847 "EHLO db3outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762600Ab3DCRUs (ORCPT ); Wed, 3 Apr 2013 13:20:48 -0400 X-Forefront-Antispam-Report: CIP:157.56.236.101;KIP:(null);UIP:(null);IPV:NLI;H:BY2PRD0510HT004.namprd05.prod.outlook.com;RD:none;EFVD:NLI X-SpamScore: -3 X-BigFish: PS-3(zz98dI936eI1432Izz1f42h1fc6h1ee6h1de0h1202h1e76h1d1ah1d2ahzz8275dhz2fh2a8h668h839h93fhd24hd2bhf0ah1288h12a5h12a9h12bdh137ah13b6h1441h1504h1537h153bh162dh1631h1758h18e1h1946h19b5h1ad9h1b0ah1155h) From: Matthew Garrett To: Matt Fleming CC: "matt.fleming@intel.com" , "ben@decadent.org.uk" , "jwboyer@redhat.com" , "linux-efi@vger.kernel.org" , "seth.forshee@canonical.com" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" Subject: Re: [PATCH 2/2] efi: Distinguish between "remaining space" and actually used space Thread-Topic: [PATCH 2/2] efi: Distinguish between "remaining space" and actually used space Thread-Index: AQHOLuuZcipjhSHk/kmF5JR3t+omNZjEe7AAgAAKU4CAADjhAIAAAlkA Date: Wed, 3 Apr 2013 17:20:30 +0000 Message-ID: <1365009630.19098.16.camel@x230> References: <515150EC.7040203@redhat.com> <1364829240-26475-1-git-send-email-matthew.garrett@nebula.com> <1364829240-26475-2-git-send-email-matthew.garrett@nebula.com> <515C2A86.6070606@console-pimps.org> <1364996911.19098.9.camel@x230> <515C62E6.1070004@console-pimps.org> In-Reply-To: <515C62E6.1070004@console-pimps.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.255.84.4] Content-Type: text/plain; charset="utf-8" Content-ID: <96B0B8E853769340B45CAFFFF359E053@namprd05.prod.outlook.com> MIME-Version: 1.0 X-OriginatorOrg: nebula.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id r33HKmC0030171 Content-Length: 1495 Lines: 32 On Wed, 2013-04-03 at 18:12 +0100, Matt Fleming wrote: > The solution you're proposing has the same downsides as 3) - we risk > having to tweak things either way. The difference is that in the case of > 3) the tweaking is adding entries to the whitelist, whereas tweaking > your solution has more chance of introducing further unwanted > regressions because you'd be tweaking an algorithm, an algorithm that > relies on the internal implementation of the variable storage code. We *risk* having to tweak things, and we fail on the side of safety. > > Dealing with firmware is hard. This fixes (1) without leaving us with > > (2), which seems like a net win. > > I'm not convinced that implementing 3) would inevitably lead to 2), > provided that we apply a bit of common sense when adding entries. I'm > not advocating some kind of flag day where we add umpteen machines to > the whitelist. > > For reference, I just pushed two patches to the 'whitelist' branch at, > > git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git > > which should hopefully illustrate the kind of thing that I'm talking about. I don't think that works. People are complaining that we broke some Thinkpads as well, but we also have reports that Thinkpads can be bricked if we use too much space. -- Matthew Garrett | mjg59@srcf.ucam.org ????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?