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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 1DE14C169C4 for ; Wed, 30 Jan 2019 01:36:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E027E21473 for ; Wed, 30 Jan 2019 01:36:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728788AbfA3Bgh (ORCPT ); Tue, 29 Jan 2019 20:36:37 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:41062 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727640AbfA3Bgg (ORCPT ); Tue, 29 Jan 2019 20:36:36 -0500 Received: from akpm3.svl.corp.google.com (unknown [104.133.8.65]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 13EF13635; Wed, 30 Jan 2019 01:36:36 +0000 (UTC) Date: Tue, 29 Jan 2019 17:36:34 -0800 From: Andrew Morton To: Andrey Ryabinin Cc: Anders Roxell , arnd@arndb.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH] lib/ubsan: default UBSAN_ALIGNMENT to not set Message-Id: <20190129173634.ee579795b227b141efc8bd30@linux-foundation.org> In-Reply-To: <8bc73bbf-6c12-7fd1-3253-676731bf5ae5@virtuozzo.com> References: <20181217150326.30933-1-anders.roxell@linaro.org> <8bc73bbf-6c12-7fd1-3253-676731bf5ae5@virtuozzo.com> X-Mailer: Sylpheed 3.6.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 11 Jan 2019 22:01:16 +0300 Andrey Ryabinin wrote: > > > On 12/17/18 6:03 PM, Anders Roxell wrote: > > When booting an allmodconfig kernel, there are a lot of false-positives. > > With a message like this 'UBSAN: Undefined behaviour in...' with a call > > trace that follows. > > > > Reworked so that when building a allmodconfig kernel that turns > > everything into '=m' or '=y' will turn off UBSAN_ALIGNMENT. > > > > Suggested-by: Arnd Bergmann > > Signed-off-by: Anders Roxell > > --- > > Acked-by: Andrey Ryabinin > Confused. Why does allmodconfig result in UBSAN warnings?