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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 E2C3EC282C2 for ; Thu, 7 Feb 2019 17:53:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2A1F2083B for ; Thu, 7 Feb 2019 17:53:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727169AbfBGRx6 (ORCPT ); Thu, 7 Feb 2019 12:53:58 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:50070 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726793AbfBGRx5 (ORCPT ); Thu, 7 Feb 2019 12:53:57 -0500 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::bf5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 0778C146D59A9; Thu, 7 Feb 2019 09:53:56 -0800 (PST) Date: Thu, 07 Feb 2019 09:53:56 -0800 (PST) Message-Id: <20190207.095356.712805621945637462.davem@davemloft.net> To: yzhai003@ucr.edu Cc: csong@cs.ucr.edu, zhiyunq@cs.ucr.edu, peppe.cavallaro@st.com, alexandre.torgue@st.com, maxime.ripard@free-electrons.com, wens@csie.org, netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net: stmmac: Variable "val" in function sun8i_dwmac_set_syscon() could be uninitialized From: David Miller In-Reply-To: References: <20190205221559.17545-1-yzhai003@ucr.edu> <20190206.201736.1146228626076916564.davem@davemloft.net> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Thu, 07 Feb 2019 09:53:57 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yizhuo Zhai Date: Wed, 6 Feb 2019 21:52:15 -0800 > Thanks, but why initialization matters here? Is performance the main > concern? Code that is unnecessary is hard to audit. People will ask "why" is it initialized? In what situations is the initialized value of "0" ever used? You are wasting people's time and energy by writing unnecessary code. 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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED 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 A86FEC282C2 for ; Thu, 7 Feb 2019 17:54:08 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7C40F2083B for ; Thu, 7 Feb 2019 17:54:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ZLABq40k" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C40F2083B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=davemloft.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Mime-Version:References:In-Reply-To: From:Subject:To:Message-Id:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=EXa+8JqO7B204gE0W0l4sEr9/tatvmrYG5g8n1P9gXA=; b=ZLABq40kfqgJNy Jf3JJ0oaUHQwNYV8v2BEJNpfIDt1oxNWs54b5GK/xctpINVBG9syt2GyI3b8qXMgpYONT5DYo7XDX YTj6jzwJUK+oCc/c235zOZ863U9s/uANLdZn5aQ+1JSbLSX8eTbCY+lWg2sTZiYn6ZAk/jqeIYK5N Wk+xISrCpwYPj66WexyZ0MUebtv1f+JJcXz2ACZXK8X1+PGBGx0tL8+6JNeE7bidb7tcdb5ZbMb9o z01jlz0OrLEiuKt4l2FJyZuRDp4AT593L+L0iUeXW7Zp6iQe3b+cXVkY6/9+1QGeJlfYViFRkjlDI Ak194IDDR2++NboeaNFQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1grnsD-0002aC-0P; Thu, 07 Feb 2019 17:54:05 +0000 Received: from shards.monkeyblade.net ([2620:137:e000::1:9]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1grns9-0002ZZ-Lz for linux-arm-kernel@lists.infradead.org; Thu, 07 Feb 2019 17:54:03 +0000 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::bf5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 0778C146D59A9; Thu, 7 Feb 2019 09:53:56 -0800 (PST) Date: Thu, 07 Feb 2019 09:53:56 -0800 (PST) Message-Id: <20190207.095356.712805621945637462.davem@davemloft.net> To: yzhai003@ucr.edu Subject: Re: [PATCH] net: stmmac: Variable "val" in function sun8i_dwmac_set_syscon() could be uninitialized From: David Miller In-Reply-To: References: <20190205221559.17545-1-yzhai003@ucr.edu> <20190206.201736.1146228626076916564.davem@davemloft.net> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Thu, 07 Feb 2019 09:53:57 -0800 (PST) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190207_095401_715199_5D8CCEF6 X-CRM114-Status: UNSURE ( 5.62 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: csong@cs.ucr.edu, alexandre.torgue@st.com, netdev@vger.kernel.org, zhiyunq@cs.ucr.edu, linux-kernel@vger.kernel.org, wens@csie.org, peppe.cavallaro@st.com, maxime.ripard@free-electrons.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Yizhuo Zhai Date: Wed, 6 Feb 2019 21:52:15 -0800 > Thanks, but why initialization matters here? Is performance the main > concern? Code that is unnecessary is hard to audit. People will ask "why" is it initialized? In what situations is the initialized value of "0" ever used? You are wasting people's time and energy by writing unnecessary code. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel