From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5735FC43441 for ; Wed, 14 Nov 2018 18:33:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2989D223DD for ; Wed, 14 Nov 2018 18:33:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2989D223DD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alien8.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732566AbeKOEhf (ORCPT ); Wed, 14 Nov 2018 23:37:35 -0500 Received: from mail.skyhub.de ([5.9.137.197]:43858 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727830AbeKOEhf (ORCPT ); Wed, 14 Nov 2018 23:37:35 -0500 X-Virus-Scanned: Nedap ESD1 at mail.skyhub.de Received: from mail.skyhub.de ([127.0.0.1]) by localhost (blast.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id RuRSoldjOf2u; Wed, 14 Nov 2018 19:33:14 +0100 (CET) Received: from zn.tnic (p200300EC2BD0D200D5714500C00E26FD.dip0.t-ipconnect.de [IPv6:2003:ec:2bd0:d200:d571:4500:c00e:26fd]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 1B7521EC037D; Wed, 14 Nov 2018 19:33:14 +0100 (CET) Date: Wed, 14 Nov 2018 19:33:15 +0100 From: Borislav Petkov To: Chao Fan Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-efi@vger.kernel.org, linux-acpi@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, keescook@chromium.org, bhe@redhat.com, msys.mizuma@gmail.com, indou.takao@jp.fujitsu.com, caoj.fnst@cn.fujitsu.com Subject: Re: [PATCH v11 3/5] x86/boot: Add get_acpi_rsdp() to parse RSDP in cmdlien from kexec Message-ID: <20181114183315.GJ13926@zn.tnic> References: <20181112094645.4879-1-fanc.fnst@cn.fujitsu.com> <20181112094645.4879-4-fanc.fnst@cn.fujitsu.com> <20181113175150.GK10502@zn.tnic> <20181114015450.GA2875@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20181114015450.GA2875@localhost.localdomain> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 14, 2018 at 09:54:50AM +0800, Chao Fan wrote: > CONFIG_KEXEC is only needed in this function. > > When searching RSDP, there are three methods in order: > 1. When booting from KEXEC, 'acpi_rsdp' is added to cmdline by KEXEC, > so it can be parsed and used. CONFIG_KEXEC is needed here. But theoretically acpi_rsdp can be supplied by the first kernel too, right? So you don't need that CONFIG_KEXEC here at all? > >Ok, let's recap: so far, for your use case you need: > > > >CONFIG_MEMORY_HOTREMOVE > >CONFIG_RANDOMIZE_BASE > >and now > >CONFIG_KEXEC > > > >So, you can clean up all that ifdeffery by defining a new config item > >CONFIG_EARLY_PARSE_RSDP or so which depends on all those three items and > >then you can do > > > >vmlinux-objs-$(CONFIG_EARLY_PARSE_RSDP) += $(obj)/acpitb.o > > > >and get rid of the most of the ifdeffery. Regardless of CONFIG_KEXEC - you still need to define a CONFIG_ symbol for your use case. We won't be parsing RSDP early on !MEMORY_HOTREMOVE machines, which is the majority. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.