From patchwork Sun Oct 25 21:48:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rasmus Villemoes X-Patchwork-Id: 285848 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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=no 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 12975C388F7 for ; Sun, 25 Oct 2020 21:48:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6DE6F222E8 for ; Sun, 25 Oct 2020 21:48:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=rasmusvillemoes.dk header.i=@rasmusvillemoes.dk header.b="ChazOuCH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1418974AbgJYVsu (ORCPT ); Sun, 25 Oct 2020 17:48:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1418969AbgJYVst (ORCPT ); Sun, 25 Oct 2020 17:48:49 -0400 Received: from mail-ej1-x642.google.com (mail-ej1-x642.google.com [IPv6:2a00:1450:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F8F0C0613D0 for ; Sun, 25 Oct 2020 14:48:48 -0700 (PDT) Received: by mail-ej1-x642.google.com with SMTP id d6so6013116ejb.11 for ; Sun, 25 Oct 2020 14:48:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rasmusvillemoes.dk; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pU074RtjEkyjZnTLMDzJX6R1Y/207D0sC+J/EOOsTPs=; b=ChazOuCH96T9UctvjyJS1OV4Cai/f9qmCl3cYdHZcpY+pBDXWlm8/YrIv4PALLSIWh wVB2meCNnIhoCJ7n1eIw3t/k0v9SltjOYSosNoa9yNHL+iYjQcy63V0zjaKyZK24UfXc me+KfcjjAQ11X2MgO18S+pxtrwQpYObQQ84tc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pU074RtjEkyjZnTLMDzJX6R1Y/207D0sC+J/EOOsTPs=; b=sfpmKjJZKvaIlW1MaPlOT4oqBZ+Cm8h1y5bluJ2QfhkMuuofJSPpT1wypz5os/yLlt 6yOthSNBS25HoydtQ4VNyhzvRhxu3TZSzdV5N32PPtbt31kASc16e0kjbBLE/uIog4uS kQDgaxgzx3NjRa8VDfsdbnw+8u8Bx/TaR8DWqKUItv+6QuZSeF3qvEuToRllRrA46kX8 SIf5XKM0vauD7koUdt++ZgmjXaty29r+SsK+5tO7iSPLulkO5SP+cUsYz8ROCKuHofYn F/tv/BNSs4uir4ZjoYkv787FuasNib02pIcxIcIYOuxcZYfIw9EdWOpb4XAt3wEYJCi5 JaNw== X-Gm-Message-State: AOAM530anlV/oTYk+DAnHu1mdMVPbpm7drSVpVw6yJ2Bjax4W9aGZKU2 D9AhVqKlqgyeXSIfMvwyiWhpqQ== X-Google-Smtp-Source: ABdhPJzRi7xuqs7AugiF/Li1BWT4PMw6UBqLt7+vT1zkoqrNiAcL19YB9zipY0qRvJy2hotXjPq/Pw== X-Received: by 2002:a17:906:5e4f:: with SMTP id b15mr13091466eju.353.1603662526661; Sun, 25 Oct 2020 14:48:46 -0700 (PDT) Received: from prevas-ravi.prevas.se (5.186.115.188.cgn.fibianet.dk. [5.186.115.188]) by smtp.gmail.com with ESMTPSA id k18sm4115867eds.93.2020.10.25.14.48.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 25 Oct 2020 14:48:46 -0700 (PDT) From: Rasmus Villemoes To: Shuah Khan , Kees Cook Cc: Petr Mladek , Willy Tarreau , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Arpitha Raghunandan <98.arpi@gmail.com>, Andy Shevchenko , Brendan Higgins , Rasmus Villemoes Subject: [PATCH 0/4] deterministic random testing Date: Sun, 25 Oct 2020 22:48:38 +0100 Message-Id: <20201025214842.5924-1-linux@rasmusvillemoes.dk> X-Mailer: git-send-email 2.23.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org This is a bit of a mixed bag. The background is that I have some sort() and list_sort() rework planned, but as part of that series I want to extend their their test suites somewhat to make sure I don't goof up - and I want to use lots of random list lengths with random contents to increase the chance of somebody eventually hitting "hey, sort() is broken when the length is 3 less than a power of 2 and only the last two elements are out of order". But when such a case is hit, it's vitally important that the developer can reproduce the exact same test case, which means using a deterministic sequence of random numbers. Since Petr noticed [1] the non-determinism in test_printf in connection with Arpitha's work on rewriting it to kunit, this prompted me to use test_printf as a first place to apply that principle, and get the infrastructure in place that will avoid repeating the "module parameter/seed the rnd_state/report the seed used" boilerplate in each module. Shuah, assuming the kselftest_module.h changes are ok, I think it's most natural if you carry these patches, though I'd be happy with any other route as well. [1] https://lore.kernel.org/lkml/20200821113710.GA26290@alley/ Rasmus Villemoes (4): prandom.h: add *_state variant of prandom_u32_max kselftest_module.h: unconditionally expand the KSTM_MODULE_GLOBALS() macro kselftest_module.h: add struct rnd_state and seed parameter lib/test_printf.c: use deterministic sequence of random numbers Documentation/dev-tools/kselftest.rst | 2 -- include/linux/prandom.h | 29 ++++++++++++++++ lib/test_bitmap.c | 3 -- lib/test_printf.c | 13 ++++--- lib/test_strscpy.c | 2 -- tools/testing/selftests/kselftest_module.h | 40 ++++++++++++++++++---- 6 files changed, 72 insertions(+), 17 deletions(-) Reviewed-by: Andy Shevchenko Reviewed-by: Petr Mladek Reviewed-by: Petr Mladek Reviewed-by: Petr Mladek