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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 59316C67863 for ; Wed, 24 Oct 2018 14:24:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2023B2082F for ; Wed, 24 Oct 2018 14:24:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Fq4xOPit" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2023B2082F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.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 S1726971AbeJXWw2 (ORCPT ); Wed, 24 Oct 2018 18:52:28 -0400 Received: from mail-lf1-f67.google.com ([209.85.167.67]:40250 "EHLO mail-lf1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726426AbeJXWw1 (ORCPT ); Wed, 24 Oct 2018 18:52:27 -0400 Received: by mail-lf1-f67.google.com with SMTP id n3-v6so4125907lfe.7; Wed, 24 Oct 2018 07:24:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=EacAJt177YLzPE8oeya/HZifyz3262DmkdK5FVCZxak=; b=Fq4xOPithePGaeg35/vJrK9nJS5UZ2GgnIZ6h4wUg/fCMTfD+fFsWimmX8c+OW1diu YgVrk214QPrbcJgRxBgYcLkifBsIe+1Z4MMzAxmhJzOLIOPoFoujBKn25IuPF2knOhaC snjq4gOte+Y7fDPqTjAEdTgnbIcnmuPCgubAhCVC03dhBq91vX8Q9BFAng3ADN6/5DvO FNuqKCNCRvBuVskYqvn1ZsbPI26g2EwRcqj7fWA8nBi2dYfu6CF0kFBMBnLhuOhJ0qab ntqaBG/H4vy4RF23pL5iQiQ+UJVDVuc/xwHEiBRvcYKetGrt89CNOgQJMxYOu+66Djv5 aI8g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=EacAJt177YLzPE8oeya/HZifyz3262DmkdK5FVCZxak=; b=PlWp90SuK7oOUBlLO43ZAvcoAVgFVs9D7nR58xrtPH0YRRAgoAiyUthNRiHAh+pL5Q i0fMj/LRR/DHkzn2tBtyrpV7IVgQZGfZ6luuidyQnI92MnCbhopOvM/8PdzmPT+mmjj9 g2hS9B/efgtUG2TspgwbfTYN9/aPfLue+wmXJAvk75j9MFYiZ5S/0pwixw/5NwuMVssp 9MHoHnPzu1XtR20uQM5bODcjzIGwV99+SrEgNip61NoRUs+VKg/dN5N/oN/rbly5GRMt T8VwWDpfcoN60pxSbxkCp5ibGK9xCnwa9XeDYx0oVkziU5mnk4e1ZKHwJJAag1wQgu1K MZwQ== X-Gm-Message-State: ABuFfojTrMNBGTIPsLjxGXQcamZXQocD+KMO9mlkJGYbs3+BpvrWbxIc BIASu5nWLwf5gZ+3EjNmyxtyYhPKV8E= X-Google-Smtp-Source: ACcGV62R7eUxS0xluqH27JngGN4Hn0g+MRp8GFJ098I3bbjq86ku0WSZ3MIxWfCItmTTIGXcA5eeEQ== X-Received: by 2002:ac2:41d8:: with SMTP id d24-v6mr14643936lfi.138.1540391045923; Wed, 24 Oct 2018 07:24:05 -0700 (PDT) Received: from [10.222.93.64] ([212.213.198.112]) by smtp.gmail.com with ESMTPSA id q5-v6sm760455ljh.60.2018.10.24.07.24.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 24 Oct 2018 07:24:05 -0700 (PDT) Subject: Re: [PATCH 06/17] prmem: test cases for memory protection To: Randy Dunlap , Mimi Zohar , Kees Cook , Matthew Wilcox , Dave Chinner , James Morris , Michal Hocko , kernel-hardening@lists.openwall.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org Cc: igor.stoppa@huawei.com, Dave Hansen , Jonathan Corbet , Laura Abbott , Vlastimil Babka , "Kirill A. Shutemov" , Andrew Morton , Pavel Tatashin , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20181023213504.28905-1-igor.stoppa@huawei.com> <20181023213504.28905-7-igor.stoppa@huawei.com> From: Igor Stoppa Message-ID: <00461c0a-a214-1984-5614-c7a4a2a7ff83@gmail.com> Date: Wed, 24 Oct 2018 17:24:03 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 24/10/18 06:27, Randy Dunlap wrote: > a. It seems backwards (or upside down) to have a test case select a feature (PRMEM) > instead of depending on that feature. > > b. Since PRMEM depends on MMU (in patch 04/17), the "select" here could try to > enabled PRMEM even when MMU is not enabled. > > Changing this to "depends on PRMEM" would solve both of these issues. The weird dependency you pointed out is partially caused by the incompleteness of PRMEM. What I have in mind is to have a fallback version of it for systems without MMU capable of write protection. Possibly defaulting to kvmalloc. In that case there would not be any need for a configuration option. > c. Don't use "default n". That is already the default. ok -- igor