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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 746DEC32792 for ; Wed, 24 Aug 2022 08:16:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235057AbiHXIQD (ORCPT ); Wed, 24 Aug 2022 04:16:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54512 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231846AbiHXIQA (ORCPT ); Wed, 24 Aug 2022 04:16:00 -0400 Received: from mail-ed1-x532.google.com (mail-ed1-x532.google.com [IPv6:2a00:1450:4864:20::532]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 376A37AC25; Wed, 24 Aug 2022 01:15:59 -0700 (PDT) Received: by mail-ed1-x532.google.com with SMTP id b44so784504edf.9; Wed, 24 Aug 2022 01:15:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc; bh=t+aZeiVlAe5lh3K/X4ugpJOclmyPgg9VuIl3dEAp86Y=; b=RwDOce9fW9ntXysRk36Zwo/dNQgieL4D1Psds2402Ua9G612KbPfZ3ywrawVqJ1LG9 BoR61Fd7PcYWIU7t9kei0WDtZ7GFA98MqONFcnkWXf8/WoM9NvZNZpuiukjkP9z31xFd poQ3TPC8/YnhKDMUBPb2NH/eKgwBpvrFjZGuAptTXvdDt9yGyypjFl+nXQGYCL6TodmB SCRfQZ5Ll0QReowdWBRx27ySciQegCzT8pq4b3oR2OEX3Z8jCSfMnkX7Flm/826/VB8i vjt1jVPgPXGRyRTT9PRL0fN1VpRAe99IpnzK7AkQGn/iSw4EF6/dR8dsindF52H6qrBD 0B/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc; bh=t+aZeiVlAe5lh3K/X4ugpJOclmyPgg9VuIl3dEAp86Y=; b=HepzZuca/tU//pWSWA+V1DeynOurr/PH9kyx8xw1+1eiYAXOVfjjY58U/BTJzygADm 23GNJyTzlWVLFKqN6g1uYpHgUyCNfki4/gVgCYbfLBbqM3z3p3v9hQoUtUQCZ3Byt69o sC8Un8JWp3iEEtFwxtGb17F6ZN3o1wvkpsnkU6IT8gkpAWI/lA1V3ZLQxQB3wxUvKISx /Hl3QQY0R73b3lJG2S9uaemiF4HuoYoanzYvk0iQA9CKfXEGiWaGFZVBDGZZBpA5l/Kx FduafUH0pjM8zxpRQMpUglrobPoFfWdDUZkh40p3YgUOk3LyFPdAvibyBrMFh1ChTVxb 0TKw== X-Gm-Message-State: ACgBeo1s+AHDdDao+7NGXmWx8f20PeJUWX+qCBU4L3outYOBIMrBX66F Gx5eMYqd+TDRXWKTKOA46zM= X-Google-Smtp-Source: AA6agR5WH9cs54GXa7c0sIrJtFNUOlFjguUIT6fJ54OYlQdQkrAW01KvKXoTr/lw8ix8/uTgzgKCRg== X-Received: by 2002:a05:6402:e98:b0:441:a982:45bc with SMTP id h24-20020a0564020e9800b00441a98245bcmr6471619eda.239.1661328957691; Wed, 24 Aug 2022 01:15:57 -0700 (PDT) Received: from [172.17.235.233] (nata195.ugent.be. [157.193.240.195]) by smtp.gmail.com with ESMTPSA id f14-20020a170906c08e00b00711edab7622sm839529ejz.40.2022.08.24.01.15.56 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 24 Aug 2022 01:15:57 -0700 (PDT) Message-ID: <1ce29a1e-2db7-2953-b71e-c0408559ecff@gmail.com> Date: Wed, 24 Aug 2022 10:15:56 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH] infiniband: remove unnecessary null check Content-Language: en-US To: cgel.zte@gmail.com, dennis.dalessandro@cornelisnetworks.com Cc: jgg@ziepe.ca, leon@kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, Minghao Chi , Zeal Robot References: <20220824080503.221680-1-chi.minghao@zte.com.cn> From: Niels Dossche In-Reply-To: <20220824080503.221680-1-chi.minghao@zte.com.cn> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/24/22 10:05, cgel.zte@gmail.com wrote: > From: Minghao Chi > > container_of is never null, so this null check is > unnecessary. > > Reported-by: Zeal Robot > Signed-off-by: Minghao Chi > --- > drivers/infiniband/sw/rdmavt/vt.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/drivers/infiniband/sw/rdmavt/vt.c b/drivers/infiniband/sw/rdmavt/vt.c > index 59481ae39505..b2d83b4958fc 100644 > --- a/drivers/infiniband/sw/rdmavt/vt.c > +++ b/drivers/infiniband/sw/rdmavt/vt.c > @@ -50,8 +50,6 @@ struct rvt_dev_info *rvt_alloc_device(size_t size, int nports) > struct rvt_dev_info *rdi; > > rdi = container_of(_ib_alloc_device(size), struct rvt_dev_info, ibdev); > - if (!rdi) > - return rdi; > > rdi->ports = kcalloc(nports, sizeof(*rdi->ports), GFP_KERNEL); > if (!rdi->ports) I believe this patch is incorrect because "_ib_alloc_device" may return a null pointer. Note that the first member of "rvt_dev_info" is "ib_device", so the check on container_of effectively checks if the allocation failed, which is necessary to check.