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=-12.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 6B3FAC2B9F7 for ; Mon, 24 May 2021 23:30:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49EE261026 for ; Mon, 24 May 2021 23:30:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229554AbhEXXbf (ORCPT ); Mon, 24 May 2021 19:31:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229668AbhEXXbd (ORCPT ); Mon, 24 May 2021 19:31:33 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A5C5EC061574 for ; Mon, 24 May 2021 16:30:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description; bh=825KHTAJ6S5hmvjoq/3MHUuy0wqdt4KWOS5cZHU37N8=; b=BLRN0gbYyGLk4jZKOqDQJ4Q6MI +wlelqt/qEFqZPeqZutZSLlBu1zyPjnfIQGSmdJWoTN6O+OOrOYYFqfHbu6yfvPC1f+nwRJcVkctZ lDvjsKBdlyuIsX/qlE+Ql4T5bzrRy7b6KNehCUOvk/s0HuSldO96/GTPCaHZoFe9sTjyFOp2KMhed OqLws/PRUk85mlsrHiuHlcE1VgdJ9CBc2Vl16kS99OA3KDcdOuZl7eIkysU85RDkSXqfVpbpp80AW vz+5QBd4bp8TYQyzkmduBkZ1fcfvsOef8rcIqCaloFc58wnqMH7B85yW984PazEu1+4K7ce7en2UJ O18gGx0w==; Received: from [2601:1c0:6280:3f0::7376] by bombadil.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1llK1J-002LXi-Rt; Mon, 24 May 2021 23:30:02 +0000 Subject: Re: [PATCH] lib/math/rational.c: Fix divide by zero To: Daniel Latypov Cc: Andy Shevchenko , Trent Piepho , Linux Kernel Mailing List , andy@kernel.org, Andrew Morton , Oskar Schirmer , Yiyuan Guo References: <20210523001806.3927609-1-tpiepho@gmail.com> From: Randy Dunlap Message-ID: Date: Mon, 24 May 2021 16:30:00 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/24/21 3:56 PM, Daniel Latypov wrote: > On Mon, May 24, 2021 at 3:04 PM Randy Dunlap wrote: >> >> On 5/24/21 9:55 AM, Daniel Latypov wrote: >>> diff --git a/lib/math/Kconfig b/lib/math/Kconfig >>> index f19bc9734fa7..20460b567493 100644 >>> --- a/lib/math/Kconfig >>> +++ b/lib/math/Kconfig >>> @@ -15,3 +15,14 @@ config PRIME_NUMBERS >>> >>> config RATIONAL >>> bool >>> + >>> +config RATIONAL_KUNIT_TEST >>> + tristate "KUnit test for rational number support" if !KUNIT_ALL_TESTS >>> + # depends on KUNIT && RATIONAL # this is how it should work, but >>> + depends on KUNIT >>> + select RATIONAL # I don't grok kconfig enough to know why this >> >> Only to set the symbol CONFIG_RATIONAL. >> Then when 'make' descends into the lib/math/ subdir and looks at its Makefile, >> it will decide to build the binary rational.o. >> >> obj-$(CONFIG_RATIONAL) += rational.o >> > > Ack, I understand that much. Oh! Clearly I misunderstood the problem. I had to look thru 60 config files before I found one where CONFIG_RATIONAL was not set. And I'm still not sure, but I believe that it's because it has to be set by some other Kconfig entry doing a 'select' on it. Here are the kconfigs that select it (on i386, where I found it not set): - COMMON_CLK [=n] && !HAVE_LEGACY_CLK [=n] - SERIAL_8250_LPSS [=n] && TTY [=n] && HAS_IOMEM [=y] && SERIAL_8250 [=n] && PCI [=n] && (X86 [=y] || COMPILE_TEST [=y]) - SERIAL_8250_MID [=n] && TTY [=n] && HAS_IOMEM [=y] && SERIAL_8250 [=n] && PCI [=n] && (X86 [=y] || COMPILE_TEST [=y]) - SERIAL_IMX [=n] && TTY [=n] && HAS_IOMEM [=y] && (ARCH_MXC || COMPILE_TEST [=y]) - VIDEO_V4L2 [=n] && MEDIA_SUPPORT [=n] && (I2C [=y] || I2C [=y]=n) && VIDEO_DEV [=n] - SND_SOC_ROCKCHIP_PDM [=n] && SOUND [=n] && !UML && SND [=n] && SND_SOC [=n] && CLKDEV_LOOKUP [=n] && SND_SOC_ROCKCHIP [=n] - COMMON_CLK_QCOM [=n] && COMMON_CLK [=n] && OF [=y] && (ARCH_QCOM || COMPILE_TEST [=y]) but my test config has none of those enabled, so I cannot set RATIONAL. I guess the easiest solution is to have KUNIT or some sub-KUNIT test just select RATIONAL. > My confusion is why this doesn't work: > > $ ./tools/testing/kunit/kunit.py run --kunitconfig /dev/stdin < CONFIG_KUNIT=y > CONFIG_RATIONAL=y > EOF > ... > ERROR:root:Provided Kconfig is not contained in validated .config. > Following fields found in kunitconfig, but not in .config: > CONFIG_RATIONAL=y > > What it's complaining about is that `make ARCH=um olddefconfig` is > leaving CONFIG_RATIONAL=y unset. > > Stripping out kunit.py, it's this: > > $ echo -e 'CONFIG_KUNIT=y\nCONFIG_RATIONAL=y' > .kunit/.config > $ make ARCH=um olddefconfig O=.kunit > $ grep RATIONAL .kunit/.config > > I'm not versed in Kconfig enough to know why CONFIG_RATIONAL=y is > getting removed. > >> >>> is necessary >>> + default KUNIT_ALL_TESTS >>> + help >>> + This builds unit tests for the rational number support. >>> + >>> + If unsure, say N. -- ~Randy