From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755974Ab2IFOSt (ORCPT ); Thu, 6 Sep 2012 10:18:49 -0400 Received: from mga09.intel.com ([134.134.136.24]:43850 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754864Ab2IFOSr (ORCPT ); Thu, 6 Sep 2012 10:18:47 -0400 Subject: Re: [RFC,PATCH v2] efi: Add support for a UEFI variable filesystem From: Matt Fleming To: Jeremy Kerr Cc: linux-kernel@vger.kernel.org, Matthew Garrett , "H. Peter Anvin" , Matt Domsch In-Reply-To: <1346910035.47691.188651047712.1.gpush@pecola> References: <1346910035.47691.188651047712.1.gpush@pecola> Content-Type: text/plain; charset="UTF-8" Organization: Intel Corporation (UK) Ltd. - Registered No. 1134945 - Pipers Way, Swindon SN3 1RJ Date: Thu, 06 Sep 2012 15:18:40 +0100 Message-ID: <1346941120.4244.82.camel@mfleming-mobl1.ger.corp.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.32.3 (2.32.3-1.fc14) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2012-09-06 at 13:40 +0800, Jeremy Kerr wrote: > From: Matthew Garrett > > The existing EFI variables code only supports variables of up to 1024 > bytes. This limitation existed in version 0.99 of the EFI specification, > but was removed before any full releases. Since variables can now be > larger than a single page, sysfs isn't the best interface for this. So, > instead, let's add a filesystem. Variables can be read, written and > created, with the first 4 bytes of each variable representing its UEFI > attributes. The create() method doesn't actually commit to flash since > zero-length variables can't exist per-spec. > > Updates from Jeremy Kerr . > > Signed-off-by: Matthew Garrett > Signed-off-by: Jeremy Kerr > > --- > v2: Add check for < 4-byte writes Am I correct in thinking that this filesystem doesn't handle deletion of authenticated variables?