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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 DDE2FC32753 for ; Wed, 14 Aug 2019 17:46:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3AC32084D for ; Wed, 14 Aug 2019 17:46:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="HRoKkCMG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728710AbfHNRqs (ORCPT ); Wed, 14 Aug 2019 13:46:48 -0400 Received: from mail.skyhub.de ([5.9.137.197]:33292 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728169AbfHNRqs (ORCPT ); Wed, 14 Aug 2019 13:46:48 -0400 Received: from zn.tnic (p200300EC2F0BD0003850D0C8BF1AA1C5.dip0.t-ipconnect.de [IPv6:2003:ec:2f0b:d000:3850:d0c8:bf1a:a1c5]) (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 BE7B31EC0260; Wed, 14 Aug 2019 19:46:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1565804807; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=2SA+6786MPKxV9jdAfB9Q+F1WSWbXybqiA3c/b/Fyek=; b=HRoKkCMGX9XffldZ1bdQh77Ucsh/dkiDimF3tNgLqjK4pzSo/87R66h1SJtgSp22UDqUVe 9ystX6lvzqfB/NilBoEtGEhi5N1uAoID2eMpKHUszFuHLpwxwk21JMPBW91lBfiSyzHmC+ 5xV1UL/PqMyGU66c8NTryZSdeBhaTYY= Date: Wed, 14 Aug 2019 19:47:32 +0200 From: Borislav Petkov To: Matthew Garrett Cc: James Morris , LSM List , Linux Kernel Mailing List , Linux API , Josh Boyer , David Howells , Kees Cook , Dave Young , linux-acpi@vger.kernel.org Subject: Re: [PATCH V38 15/29] acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down Message-ID: <20190814174732.GD1841@zn.tnic> References: <20190808000721.124691-1-matthewgarrett@google.com> <20190808000721.124691-16-matthewgarrett@google.com> <20190814072602.GA27836@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: 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, Aug 14, 2019 at 10:14:54AM -0700, Matthew Garrett wrote: > We explicitly don't want to pay attention to the acpi_rsdp kernel > parameter in early boot except for the case of finding the SRAT table, > and we only need that if CONFIG_RANDOMIZE_BASE and > CONFIG_MEMORY_HOTREMOVE are set. However, we *do* want to tell the > actual kernel where the RSDP is if we found it via some other means, > so we can't just clear the boot parameters value. Ok. > The kernel proper will parse the command line again and will then (if > lockdown isn't enabled) override the actual value we passed up in boot > params. Yeah, ok, I see what you're doing there. AFAICT, you do that in setup_arch->acpi_boot_table_init-> ... -> acpi_os_get_root_pointer() I hope nothing needs it earlier because then we'll have to restructure again... Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.