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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 4E96CC43334 for ; Thu, 6 Sep 2018 12:02:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0BA582075B for ; Thu, 6 Sep 2018 12:02:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BA582075B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=canonical.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 S1728522AbeIFQhL (ORCPT ); Thu, 6 Sep 2018 12:37:11 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:47387 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727758AbeIFQhL (ORCPT ); Thu, 6 Sep 2018 12:37:11 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212]) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1fxsz1-0006Cc-U2; Thu, 06 Sep 2018 12:01:59 +0000 Subject: Re: [PATCH] ASoC: sgtl5000: avoid division by zero if lo_vag is zero To: Dan Carpenter Cc: Fabio Estevam , Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , alsa-devel@alsa-project.org, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org References: <20180906104152.17977-1-colin.king@canonical.com> <20180906115814.a5woyhfc5sczxksa@mwanda> From: Colin Ian King Openpgp: preference=signencrypt Autocrypt: addr=colin.king@canonical.com; prefer-encrypt=mutual; keydata= xsFNBE6TJCgBEACo6nMNvy06zNKj5tiwDsXXS+LhT+LwtEsy9EnraKYXAf2xwazcICSjX06e fanlyhB0figzQO0n/tP7BcfMVNG7n1+DC71mSyRK1ZERcG1523ajvdZOxbBCTvTitYOy3bjs +LXKqeVMhK3mRvdTjjmVpWnWqJ1LL+Hn12ysDVVfkbtuIm2NoaSEC8Ae8LSSyCMecd22d9Pn LR4UeFgrWEkQsqROq6ZDJT9pBLGe1ZS0pVGhkRyBP9GP65oPev39SmfAx9R92SYJygCy0pPv BMWKvEZS/7bpetPNx6l2xu9UvwoeEbpzUvH26PHO3DDAv0ynJugPCoxlGPVf3zcfGQxy3oty dNTWkP6Wh3Q85m+AlifgKZudjZLrO6c+fAw/jFu1UMjNuyhgShtFU7NvEzL3RqzFf9O1qM2m uj83IeFQ1FZ65QAiCdTa3npz1vHc7N4uEQBUxyXgXfCI+A5yDnjHwzU0Y3RYS52TA3nfa08y LGPLTf5wyAREkFYou20vh5vRvPASoXx6auVf1MuxokDShVhxLpryBnlKCobs4voxN54BUO7m zuERXN8kadsxGFzItAyfKYzEiJrpUB1yhm78AecDyiPlMjl99xXk0zs9lcKriaByVUv/NsyJ FQj/kmdxox3XHi9K29kopFszm1tFiDwCFr/xumbZcMY17Yi2bQARAQABzSJDb2xpbiBLaW5n IDxjb2xpbi5raW5nQHVidW50dS5jb20+wsF3BBMBCAAhBQJPCrjvAhsDBQsJCAcDBRUKCQgL BRYCAwEAAh4BAheAAAoJEGjCh9/GqAImjVsP/iA8hDQy7LlMYepND9tKJD2haNLmsBC+yuxX BybYprtSjwvMbx6CtmtiJ4nGfdBzbZv3xOJPr/n6wxrdfGHEFn0W8Au97Xvk087P7alCwBXz y1Hk1aTlhLOGunOLv6SWRYRUAHvWEoVlxPSo2UNJ6D01d9tc7IJU08MlAl+u048S6625G5SG tfOJpFyGqaWGazMpkYdbJuY9acNAQAl1GzZPDCyLrxaBJypqmp3W+rb7m9arNRMlygevFU6e UGrR7QiVuumTGebGF9D63H9LD0E/1EhOA4QWHq1/u7CXLr9qo1YyAUtYAICs0wyRbI6wWPyi 5IyOTiWCVP3qSxV4JR8qq8JhGEwxS5fEB76r+XGxcL7qqiQmVx3bkjlT6FnnanPcD7RsMOAg NcpeftVsqignFPA3XHaDeew4t99ef+wKwiiyU7jqduvSt8amLVip5dxN1TYKqWPauIHL3E2A KIKuqsZ9ftUJ3NXClAfI3EHPMYbok6b04nZSWmBttKHr8YkVF5b4jrabMLlVoCg+DGYffyDS YDwy9FPvJWkt6nffUXciearieSlHEt3f12CPp6OOR8yFZWlISYKdD9PDzXP9kJYTEWnr7dD3 feEZK+J9N5wpCU7HvfrA5HCOMJgf8Dcfscrj9H2Qp8vbErMP7jZ6OYapCOV5MZS6W57wlG2k zsFNBE6TJCgBEADF+hz+c0qF0R58DwiM8M/PopzFu5ietBpl0jUzglaKhMZKKW7lAr4pzeE4 PgJ4ZwQd0dSkx63hRqM963Fe35iXrreglpwZxgbbGluRJpoeoGWzuUpXE6Ze0A2nICFLk79a YHsFRwnKyol9M0AyZHCvBXi1HAdj17iXerCYN/ZILD5SO0dDiQl570/1Rp3d1z0l16DuCnK+ X3I7GT8Z9B3WAr6KCRiP0Grvopjxwkj4Z191mP/auf1qpWPXEAPLVAvu5oM7dlTIxX7dYa6f wlcm1uobZvmtXeDEuHJ3TkbFgRHrZwuh50GMLguG1QjhIPXlzE7/PBQszh5zGxPj8cR81txs 6K/0GGRnIrPhCIlOoTU8L+BenxZF31uutdScHw1EAgB6AsRdwdd8a9AR+XdhHGzQel8kGyBp 4MA7508ih0L9+MBPuCrSsccjwV9+mfsTszrbZosIhVpBaeHNrUMphwFe9HbGUwQeS6tOr+py bOtNUHeiJ5aU3Npo3eZkWVGePP2O4vr8rjVQ1xZMIWA18xUaLTvVSarV7/IqjLb0uMTz6Ng7 SceqjsgxO4J35pPOCG8gy85Tmd5NKe46K1xGsNG2zzfXQ6cNkofUyQFGVbLCtdfQyWV7+dgU nOnPhrTKpFfJ5lnWpLpze0LfyW03CpWx9x4yMlwcvIFw2hLaOQARAQABwsFfBBgBCAAJBQJO kyQoAhsMAAoJEGjCh9/GqAImeJYP/jdppMeb7AZnLGVXd8rN7CLBtfMOkXCWaOUhjMRAY7dV IMiF1iPZc6SgiiMSsdG7JJhMjMuLTxA0kX2Z6P0+6dZlO4bDOKMIv4nNGhgSj9NuSKJPRiyi XKKD/wNnPXVFdBZsoHnEXGyAFGnidu4KLUJIiSm4tHJdoMk0ZaJSmwt0dtytuC1IWH8eIaVo /Ah6FxCaznRzvGNFx+9Ofcc7+aMZ15dkg9XagOuiDZ1/r6VuEw9ovnkDT4H5BAsysxo/qykX 4XQ2RQSY/P3td9WNLeXLvt1aJNRcwcIEKgZ5AO3YQbEJt1dEfCU7TAKiRpsjnC/iQiQHGt2I vNci8oZmM3EQEi7yZqD07A6dpGTnRq9OQ7fGhj0SS99yZvooH3fBIHA2LRuvhfDAgTrpbU0w LvkAIo0T2b9SoRCV8FEpHvR2b86NbTU5WN4eqZQbAbnxC7tJp6kLx2Zn2uQMvfXRfnS9R1ja etvpk3h7F+r/RAAh+EvgsPUNaiRJRRLvf9bxTQZhmNrw79eIFNsRIktniLyomJf2+WPOUECz h1lfLqe9yiuUKv+m5uAalXdayhiPbp/JHs1EDRgSq3tiirOsKrh/KMpwz/22qGMRBjFwYBhf 6ozgujmPlO5DVFtzfwOydzNlXTky7t4VU8yTGXZTJprIO+Gs72Q1e+XVIoKl3MIx Message-ID: <43293b8e-5b9d-ff51-aa3f-eb1a7b9490aa@canonical.com> Date: Thu, 6 Sep 2018 13:01:58 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180906115814.a5woyhfc5sczxksa@mwanda> Content-Type: text/plain; charset=utf-8 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 On 06/09/18 12:58, Dan Carpenter wrote: > On Thu, Sep 06, 2018 at 11:41:52AM +0100, Colin King wrote: >> From: Colin Ian King >> >> In the case where lo_vag <= SGTL5000_LINE_OUT_GND_BASE, lo_vag >> is set to zero and later vol_quot is computed by dividing by >> lo_vag causing a division by zero error. Fix this by avoiding >> a zero division and set vol_quot to zero in this specific case >> so that the lowest setting for i is correctly set. >> > > This is a very clever patch. How did you find the bug? trawling through a lot of false positives from a recent cppcheck run > > regards, > dan carpenter >