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=-2.3 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 96B81C43441 for ; Wed, 10 Oct 2018 09:06:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4ED48214DA for ; Wed, 10 Oct 2018 09:06:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4ED48214DA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.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 S1727444AbeJJQ1g (ORCPT ); Wed, 10 Oct 2018 12:27:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51366 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726525AbeJJQ1g (ORCPT ); Wed, 10 Oct 2018 12:27:36 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B9EBD307C714; Wed, 10 Oct 2018 09:06:23 +0000 (UTC) Received: from localhost (ovpn-8-16.pek2.redhat.com [10.72.8.16]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D6ED562672; Wed, 10 Oct 2018 09:06:22 +0000 (UTC) Date: Wed, 10 Oct 2018 17:06:20 +0800 From: Baoquan He To: Borislav Petkov Cc: Chao Fan , Ingo Molnar , Thomas Gleixner , linux-kernel@vger.kernel.org, x86@kernel.org, linux-efi@vger.kernel.org, linux-acpi@vger.kernel.org, mingo@redhat.com, hpa@zytor.com, keescook@chromium.org, rjw@rjwysocki.net, lenb@kernel.org, ard.biesheuvel@linaro.org, indou.takao@jp.fujitsu.com, caoj.fnst@cn.fujitsu.com, Masayoshi Mizuma Subject: Re: [PATCH v8 0/3] x86/boot/KASLR: Parse ACPI table and limit kaslr in immovable memory Message-ID: <20181010090620.GF25297@MiWiFi-R3L-srv> References: <20181010084119.17539-1-fanc.fnst@cn.fujitsu.com> <20181010085920.GB5533@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181010085920.GB5533@zn.tnic> User-Agent: Mutt/1.9.1 (2017-09-22) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Wed, 10 Oct 2018 09:06:24 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Boris, On 10/10/18 at 10:59am, Borislav Petkov wrote: > ... and we just picked up > > https://lkml.kernel.org/r/20181001140843.26137-1-msys.mizuma@gmail.com > > and without having looked at the rest of your stuff, if people accept > your solution, we don't need the silly parameter anymore, right? > > Which means, we should not rush the whole thing yet until the whole > KASLR vs movable memory gets solved properly. Masa's patches solves the problem in memory region KASLR which later hot added memory may be big than the default padding 10 TB. Chao's patches is trying to fix a conflict between 'movable_node' and kernel text KASLR. If 'movable_node' specified, we rely on SRAT to get which memory region is movable or immovable, and movable region can be hot removed. But if kernel is randomized into movable memory, it can't be hot removed any more, this is a regression after KASLR introduced. So this is a different issue than Masa's. Thanks Baoquan