Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755944AbdGYAYD (ORCPT ); Mon, 24 Jul 2017 20:24:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46000 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755525AbdGYAXy (ORCPT ); Mon, 24 Jul 2017 20:23:54 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 5A6074A6E6 Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=bhe@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 5A6074A6E6 Date: Tue, 25 Jul 2017 08:23:48 +0800 From: Baoquan He To: Matt Fleming Cc: Ingo Molnar , linux-kernel@vger.kernel.org, x86@kernel.org, keescook@chromium.org, tglx@linutronix.de, hpa@zytor.com, izumi.taku@jp.fujitsu.com, fanc.fnst@cn.fujitsu.com, thgarnie@google.com, n-horiguchi@ah.jp.nec.com Subject: Re: [PATCH v6 RESEND] x86/boot/KASLR: Restrict kernel to be randomized in mirror regions Message-ID: <20170725002348.GD24530@x1> References: <1500542189-15779-1-git-send-email-bhe@redhat.com> <20170721103757.hc74czr3mfunrv6c@gmail.com> <20170721131956.GK2344@x1> <20170724133410.GC11076@codeblueprint.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170724133410.GC11076@codeblueprint.co.uk> User-Agent: Mutt/1.7.0 (2016-08-17) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 25 Jul 2017 00:23:53 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 631 Lines: 17 On 07/24/17 at 02:34pm, Matt Fleming wrote: > On Fri, 21 Jul, at 09:19:56PM, Baoquan He wrote: > > > > There are places where the efi map is getting and used like this. E.g > > in efi_high_alloc() of drivers/firmware/efi/libstub/efi-stub-helper.c. > > EFI developers worry the size of efi_memory_desc_t could not be the same > > as e->efi_memdesc_size? > > > > Hi Matt, > > > > Could you help have a look at this? > > You're exactly right. The code guards against the size of the > efi_memory_desc_t struct changing. The UEFI spec says to traverse the > memory map this way. Thanks a lot, Matt. Then I will keep using the way.