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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,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 74B67C43382 for ; Tue, 25 Sep 2018 01:13:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F14720C0A for ; Tue, 25 Sep 2018 01:13:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1F14720C0A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=cn.fujitsu.com 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 S1726944AbeIYHSS (ORCPT ); Tue, 25 Sep 2018 03:18:18 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:20985 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726059AbeIYHSS (ORCPT ); Tue, 25 Sep 2018 03:18:18 -0400 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="45300333" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 25 Sep 2018 09:13:19 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id 087EF4B6AE13; Tue, 25 Sep 2018 09:13:21 +0800 (CST) Received: from localhost.localdomain (10.167.225.56) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.408.0; Tue, 25 Sep 2018 09:13:26 +0800 Date: Tue, 25 Sep 2018 09:12:46 +0800 From: Chao Fan To: Kees Cook CC: linux-efi , ACPI Devel Maling List , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , X86 ML , LKML , Baoquan He , "Rafael J. Wysocki" , Len Brown , Ard Biesheuvel , , Subject: Re: [PATCH v7 1/3] x86/boot: Add acpitb.c to parse acpi tables Message-ID: <20180925011246.GB12561@localhost.localdomain> References: <20180913104629.5179-1-fanc.fnst@cn.fujitsu.com> <20180913104629.5179-2-fanc.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-Originating-IP: [10.167.225.56] X-yoursite-MailScanner-ID: 087EF4B6AE13.AB386 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: fanc.fnst@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 22, 2018 at 08:45:12AM -0700, Kees Cook wrote: >On Thu, Sep 13, 2018 at 3:46 AM, Chao Fan wrote: >> There is a bug that kaslr may randomly chooses some positions >> which are located in movable memory regions. This will break memory >> hotplug feature and make the movable memory chosen by KASLR can't be >> removed. So dig SRAT table from ACPI tables to get memory information. >> >> Imitate the ACPI code of parsing ACPI tables to dig and read ACPI >> tables. Since some operations are not needed here, functions are >> simplified. Functions will be used to dig only SRAT tables to get >> information of memory, so that KASLR can the memory in immovable node. >> >> And also, these functions won't influence the initialization of >> ACPI after start_kernel(). >> >> Since use physical address directely, so acpi_os_map_memory() >> and acpi_os_unmap_memory() are not needed. >> >> Signed-off-by: Chao Fan >> --- >> arch/x86/boot/compressed/Makefile | 4 + >> arch/x86/boot/compressed/acpitb.c | 401 ++++++++++++++++++++++++++++++ > >Does this logic live anywhere else in the kernel already? (i.e. could >other code be reused?) Live in uncompressec period, but not completely same. The map between physical address and virtual address is not needed here. So I thins it's hard to reuse, that's why I made this new file. Thanks, Chao Fan > >-Kees > >-- >Kees Cook >Pixel Security > >