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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 21691C43441 for ; Thu, 11 Oct 2018 01:31:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC4392087A for ; Thu, 11 Oct 2018 01:30:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC4392087A 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 S1726189AbeJKIzt (ORCPT ); Thu, 11 Oct 2018 04:55:49 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:7526 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726007AbeJKIzt (ORCPT ); Thu, 11 Oct 2018 04:55:49 -0400 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="45900142" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Oct 2018 09:30:57 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id 060224B6ED81; Thu, 11 Oct 2018 09:30:56 +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; Thu, 11 Oct 2018 09:31:01 +0800 Date: Thu, 11 Oct 2018 09:30:16 +0800 From: Chao Fan To: Borislav Petkov CC: , , , , , , , , , , , , , Subject: Re: [PATCH v8 0/3] x86/boot/KASLR: Parse ACPI table and limit kaslr in immovable memory Message-ID: <20181011013015.GA6667@localhost.localdomain> References: <20181010084119.17539-1-fanc.fnst@cn.fujitsu.com> <20181010171616.GD5533@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20181010171616.GD5533@zn.tnic> User-Agent: Mutt/1.10.1 (2018-07-13) X-Originating-IP: [10.167.225.56] X-yoursite-MailScanner-ID: 060224B6ED81.AB533 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 Wed, Oct 10, 2018 at 07:16:16PM +0200, Borislav Petkov wrote: >On Wed, Oct 10, 2018 at 04:41:16PM +0800, Chao Fan wrote: >> In the earliest time, I tried to dig ACPI tabls to solve this problem. >> But I didn't splite the code in 'compressed/' and ACPI code, so the patch >> is hard to follow so refused by community. >> Somebody suggest to add a kernel parameter to specify the >> immovable memory so that limit kaslr in these regions. Then I make >> a new patchset. After several versions, Ingo gave a suggestion: >> https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1634024.html >> Follow Ingo's suggestion, imitate the ACPI code to parse the acpi >> tables, so that the kaslr can get necessary memory information in >> ACPI tables. >> I think ACPI code is an independent part, so copy the codes >> and functions to 'compressed/' directory, so that kaslr won't >> influence the initialization of ACPI. > >You say "copy". I'm still about to look at the code but can those >functions be carved out in a separate compilation unit which ACPI *and* >KASLR can both link with so that there's no duplication? Sorry for my poor English, I used 'copy' but they are not same. Maybe 'imitate' is better. Just like I said in my log, The ACPI part need to handle the map between physical address and virtual address. But in KASLR part, I remove these operations. So my code is simplified version. Thanks, Chao Fan > >-- >Regards/Gruss, > Boris. > >Good mailing practices for 400: avoid top-posting and trim the reply. > >