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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 EF95EC433B4 for ; Mon, 3 May 2021 11:58:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A515C61185 for ; Mon, 3 May 2021 11:58:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233019AbhECL7V (ORCPT ); Mon, 3 May 2021 07:59:21 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:57802 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231180AbhECL7V (ORCPT ); Mon, 3 May 2021 07:59:21 -0400 Received: from cpc154979-craw9-2-0-cust193.16-3.cable.virginm.net ([80.193.200.194] helo=[192.168.0.209]) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1ldXDW-0007KD-5g; Mon, 03 May 2021 11:58:26 +0000 Subject: Re: [PATCH] fs/btrfs: Fix uninitialized variable To: Dan Carpenter , Khaled Romdhani Cc: clm@fb.com, josef@toxicpanda.com, dsterba@suse.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org References: <20210501225046.9138-1-khaledromdhani216@gmail.com> <20210503072322.GK1981@kadam> <20210503101312.GA27593@ard0534> <20210503115515.GJ21598@kadam> From: Colin Ian King Message-ID: <7b58f7c7-1586-0e0f-4166-d5132322fe58@canonical.com> Date: Mon, 3 May 2021 12:58:25 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210503115515.GJ21598@kadam> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: kernel-janitors@vger.kernel.org On 03/05/2021 12:55, Dan Carpenter wrote: > On Mon, May 03, 2021 at 11:13:12AM +0100, Khaled Romdhani wrote: >> On Mon, May 03, 2021 at 10:23:22AM +0300, Dan Carpenter wrote: >>> On Sat, May 01, 2021 at 11:50:46PM +0100, Khaled ROMDHANI wrote: >>>> Fix the warning: variable 'zone' is used >>>> uninitialized whenever '?:' condition is true. >>>> >>>> Fix that by preventing the code to reach >>>> the last assertion. If the variable 'mirror' >>>> is invalid, the assertion fails and we return >>>> immediately. >>>> >>>> Reported-by: kernel test robot >>>> Signed-off-by: Khaled ROMDHANI >>>> --- >>> >>> This is not how you send a v4 patch... v2 patches have to apply to the >>> original code and not on top of the patched code. >>> >>> I sort of think you should find a different thing to work on. This code >>> works fine as-is. Just leave it and try to find a real bug and fix that >>> instead. >>> >>> regards, >>> dan carpenter >>> >> >> Sorry, I was wrong and I shall send a proper V4. >> >> Yes, this code works fine just a warning caught by Coverity scan analysis. > > We're going to a lot of work to silence a static checker false positive. > As a rule, I tell people to ignore the static checker when it is wrong. > > Btw, Smatch parses this code correctly and understands that the callers > only pass valid values for "mirror". ..and Coverity does report a lot of false positives, so one needs to be really sure the issue is a genuine issue rather than a warning that can be ignore. Colin > > regards, > dan carpenter >