From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755939Ab2CXTpc (ORCPT ); Sat, 24 Mar 2012 15:45:32 -0400 Received: from terminus.zytor.com ([198.137.202.10]:36400 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753258Ab2CXTpa (ORCPT ); Sat, 24 Mar 2012 15:45:30 -0400 References: <1332512984-79664-1-git-send-email-trenn@suse.de> <4F6CD79A.8020805@zytor.com> <201203240242.07724.trenn@suse.de> <4F6D2AF8.3070707@zytor.com> <20120324184238.GB13978@phenom.dumpdata.com> <4F6E1D6F.4000308@zytor.com> <20120324191718.GA3927@phenom.dumpdata.com> User-Agent: K-9 Mail for Android In-Reply-To: <20120324191718.GA3927@phenom.dumpdata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: [PATCH] ACPI: Implement overriding of arbitrary ACPI tables via initrd From: "H. Peter Anvin" Date: Sat, 24 Mar 2012 12:44:59 -0700 To: Konrad Rzeszutek Wilk CC: Thomas Renninger , eric.piel@tremplin-utc.net, vojcek@tlen.pl, dsdt@gaugusch.at, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, Lin Ming , lenb@kernel.org, robert.moore@intel.com, Al Viro , Harald Hoyer Message-ID: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org You're missing the point. Unless you have specific rules how to deal.with extensions, and what thise extensions may do, you're not adding anything. I think the simpler just use cpio idea still wins out in my mind. Konrad Rzeszutek Wilk wrote: >On Sat, Mar 24, 2012 at 12:15:59PM -0700, H. Peter Anvin wrote: >> On 03/24/2012 11:42 AM, Konrad Rzeszutek Wilk wrote: >> > >> > Probably should also have: >> > u32 version; >> > >> > in case we decide to expand this structure in the future, and: >> >> u32 type; /* 1 = file data, 2 = ACPI, 3 = microcode... */ >> >> u32 length; /* Length of data object */ >> >> }; >> > >> > and encapsulate the whole thing in a 4K union? >> > >> >> For "version" you'd have to define what happens if you see a version >> number you don't recognize, and why that is in any way better than >> changing the magic number or the type. It is something that people >like >> to throw in without thinking about it, and that is a mistake. > >I was thinking of interface version. So the first would be 1, and if >there are extensions (so version 2 for example), it should support 1 >and 2. >The idea is to expand past the structure with newer additions without >breaking the binary interface. > >> >> Forcing everything to be page-aligned may be a good idea, although >that >> assumes all bootloaders actually align them that way... > >Oh, and be 4K. >> >> > >> > Perhaps the header should be in big-endian (that is the same as the >network >> > byte order, right?) and each sub-type can define its own endian? >> > >> >> The content of the encapsulation is its own thing; it will be >different >> for different types as most of them already >> >> -hpa >> >> -- >> H. Peter Anvin, Intel Open Source Technology Center >> I work for Intel. I don't speak on their behalf. -- Sent from my mobile phone. Please excuse my brevity and lack of formatting.