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=-7.2 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_PASS,URIBL_BLOCKED,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 451C1C07E85 for ; Sun, 9 Dec 2018 10:38:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EDB6A2081F for ; Sun, 9 Dec 2018 10:38:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="khbw9s5m" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EDB6A2081F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=armlinux.org.uk 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 S1726166AbeLIKh5 (ORCPT ); Sun, 9 Dec 2018 05:37:57 -0500 Received: from pandora.armlinux.org.uk ([78.32.30.218]:33526 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726079AbeLIKh4 (ORCPT ); Sun, 9 Dec 2018 05:37:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=V28/jOgEw0hSqFM6gCHI4O7G2a25ciSSb3eLB7lLxH0=; b=khbw9s5mqaGpgqu5dCT0qs5Tt Cr6A5Zovk6sCyycQ1MT/KMIVtVmEuNPP9UmLBZ03KjFxnW7FK4uQU8Q4qsHj4ius+D3vZ69ikt08x ksav6ojQlSdHZloeLY4hlNYqV0mBcn4h5leXKu5XpjFWDnmv7Z1Nmo7Gx4+wszJoJBMpU=; Received: from n2100.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:4f86]:48890) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1gVwT5-0002Pc-Hd; Sun, 09 Dec 2018 10:37:47 +0000 Received: from linux by n2100.armlinux.org.uk with local (Exim 4.90_1) (envelope-from ) id 1gVwT0-0001yd-Q6; Sun, 09 Dec 2018 10:37:42 +0000 Date: Sun, 9 Dec 2018 10:37:40 +0000 From: Russell King - ARM Linux To: kbuild test robot Cc: Ard Biesheuvel , kbuild-all@01.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Kees Cook , Emese Revfy , Arnd Bergmann , Laura Abbott , kernel-hardening@lists.openwall.com Subject: Re: [PATCH v3] ARM: smp: add support for per-task stack canaries Message-ID: <20181209103740.GB30658@n2100.armlinux.org.uk> References: <20181206083257.9596-1-ard.biesheuvel@linaro.org> <201812091807.4emRkZ7L%fengguang.wu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201812091807.4emRkZ7L%fengguang.wu@intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Dec 09, 2018 at 06:28:11PM +0800, kbuild test robot wrote: > Hi Ard, > > I love your patch! Perhaps something to improve: Hi, This looks to me like a false warning - how can a patch touching arch code affect the result of lib/test_ubsan.c? Please can you double- check this result? Thanks. > > [auto build test WARNING on arm/for-next] > [also build test WARNING on v4.20-rc5] > [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] > > url: https://github.com/0day-ci/linux/commits/Ard-Biesheuvel/ARM-smp-add-support-for-per-task-stack-canaries/20181209-033321 > base: git://git.armlinux.org.uk/~rmk/linux-arm.git for-next > config: arm-allmodconfig (attached as .config) > compiler: arm-linux-gnueabi-gcc (Debian 7.2.0-11) 7.2.0 > reproduce: > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > # save the attached .config to linux build tree > GCC_VERSION=7.2.0 make.cross ARCH=arm > > All warnings (new ones prefixed by >>): > > lib/test_ubsan.c: In function 'test_ubsan_vla_bound_not_positive': > >> lib/test_ubsan.c:48:2: warning: ISO C90 forbids variable length array 'buf' [-Wvla] > char buf[size]; > ^~~~ > lib/test_ubsan.c: In function 'test_ubsan_out_of_bounds': > >> lib/test_ubsan.c:64:2: warning: ISO C90 forbids variable length array 'arr' [-Wvla] > volatile int arr[i]; > ^~~~~~~~ > > vim +/buf +48 lib/test_ubsan.c > > 854686f4 Jinbum Park 2018-04-10 44 > 854686f4 Jinbum Park 2018-04-10 45 static void test_ubsan_vla_bound_not_positive(void) > 854686f4 Jinbum Park 2018-04-10 46 { > 854686f4 Jinbum Park 2018-04-10 47 volatile int size = -1; > 854686f4 Jinbum Park 2018-04-10 @48 char buf[size]; > 854686f4 Jinbum Park 2018-04-10 49 > 854686f4 Jinbum Park 2018-04-10 50 (void)buf; > 854686f4 Jinbum Park 2018-04-10 51 } > 854686f4 Jinbum Park 2018-04-10 52 > 854686f4 Jinbum Park 2018-04-10 53 static void test_ubsan_shift_out_of_bounds(void) > 854686f4 Jinbum Park 2018-04-10 54 { > 854686f4 Jinbum Park 2018-04-10 55 volatile int val = -1; > 854686f4 Jinbum Park 2018-04-10 56 int val2 = 10; > 854686f4 Jinbum Park 2018-04-10 57 > 854686f4 Jinbum Park 2018-04-10 58 val2 <<= val; > 854686f4 Jinbum Park 2018-04-10 59 } > 854686f4 Jinbum Park 2018-04-10 60 > 854686f4 Jinbum Park 2018-04-10 61 static void test_ubsan_out_of_bounds(void) > 854686f4 Jinbum Park 2018-04-10 62 { > 854686f4 Jinbum Park 2018-04-10 63 volatile int i = 4, j = 5; > 854686f4 Jinbum Park 2018-04-10 @64 volatile int arr[i]; > 854686f4 Jinbum Park 2018-04-10 65 > 854686f4 Jinbum Park 2018-04-10 66 arr[j] = i; > 854686f4 Jinbum Park 2018-04-10 67 } > 854686f4 Jinbum Park 2018-04-10 68 > > :::::: The code at line 48 was first introduced by commit > :::::: 854686f4edf483db1e0d26d972bdb8fb65c8bfaa lib: add testing module for UBSAN > > :::::: TO: Jinbum Park > :::::: CC: Linus Torvalds > > --- > 0-DAY kernel test infrastructure Open Source Technology Center > https://lists.01.org/pipermail/kbuild-all Intel Corporation -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up