Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752735Ab3HUTyV (ORCPT ); Wed, 21 Aug 2013 15:54:21 -0400 Received: from mail-qa0-f52.google.com ([209.85.216.52]:46038 "EHLO mail-qa0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751836Ab3HUTyR (ORCPT ); Wed, 21 Aug 2013 15:54:17 -0400 Date: Wed, 21 Aug 2013 15:54:10 -0400 From: Tejun Heo To: Toshi Kani Cc: Zhang Yanfei , Tang Chen , konrad.wilk@oracle.com, robert.moore@intel.com, lv.zheng@intel.com, rjw@sisk.pl, lenb@kernel.org, tglx@linutronix.de, mingo@elte.hu, hpa@zytor.com, akpm@linux-foundation.org, trenn@suse.de, yinghai@kernel.org, jiang.liu@huawei.com, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com, izumi.taku@jp.fujitsu.com, mgorman@suse.de, minchan@kernel.org, mina86@mina86.com, gong.chen@linux.intel.com, vasilis.liaskovitis@profitbricks.com, lwoodman@redhat.com, riel@redhat.com, jweiner@redhat.com, prarit@redhat.com, zhangyanfei@cn.fujitsu.com, yanghy@cn.fujitsu.com, x86@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH 0/8] x86, acpi: Move acpi_initrd_override() earlier. Message-ID: <20130821195410.GA2436@htj.dyndns.org> References: <1377080143-28455-1-git-send-email-tangchen@cn.fujitsu.com> <20130821130647.GB19286@mtj.dyndns.org> <5214D60A.2090309@gmail.com> <20130821153639.GA17432@htj.dyndns.org> <1377113503.10300.492.camel@misato.fc.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1377113503.10300.492.camel@misato.fc.hp.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1461 Lines: 37 Hello, Toshi. On Wed, Aug 21, 2013 at 01:31:43PM -0600, Toshi Kani wrote: > Well, there is reason why we have earlyprintk feature today. So, let's > not debate on this feature now. There was previous attempt to support Are you saying the existing earlyprintk automatically justifies addition of more complex mechanism? The added complex of course should be traded off against the benefits of gaining ACPI based early boot. You aren't gonna suggest implementing netconsole based earlyprintk, right? > this feature with ACPI tables below. As described, it had the same > ordering issue. > > https://lkml.org/lkml/2012/10/8/498 > > There is a basic problem that when we try to use ACPI tables that > extends or replaces legacy interfaces (ex. SRAT extending e820), we hit > this ordering issue because ACPI is not available as early as the legacy > interfaces. Do we even want ACPI parsing and all that that early? Parsing SRAT early doesn't buy us much and I'm not sure whether adding ACPI earlyprintk would increase or decrease debuggability during earlyboot. It adds whole lot more code paths where things can go wrong while the basic execution environment is unstable. Why do that? Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/