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=-7.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 AC3B7C433E3 for ; Mon, 27 Jul 2020 16:09:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 913942075A for ; Mon, 27 Jul 2020 16:09:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728170AbgG0QJl (ORCPT ); Mon, 27 Jul 2020 12:09:41 -0400 Received: from smtprelay0194.hostedemail.com ([216.40.44.194]:55062 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727862AbgG0QJk (ORCPT ); Mon, 27 Jul 2020 12:09:40 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay06.hostedemail.com (Postfix) with ESMTP id BD4BF182251C0; Mon, 27 Jul 2020 16:09:39 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: stem58_2a1235a26f62 X-Filterd-Recvd-Size: 1602 Received: from XPS-9350.home (unknown [47.151.133.149]) (Authenticated sender: joe@perches.com) by omf08.hostedemail.com (Postfix) with ESMTPA; Mon, 27 Jul 2020 16:09:37 +0000 (UTC) Message-ID: <0897d9bec8865859694c917f3f72ab8fd12321ff.camel@perches.com> Subject: Re: [PATCH 2/2] media: bt8xx: avoid a useless memset From: Joe Perches To: Christophe JAILLET , mchehab@kernel.org, akpm@linux-foundation.org, rppt@kernel.org, hverkuil-cisco@xs4all.nl Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Date: Mon, 27 Jul 2020 09:09:34 -0700 In-Reply-To: <20200727135151.54757-1-christophe.jaillet@wanadoo.fr> References: <20200727135151.54757-1-christophe.jaillet@wanadoo.fr> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.36.3-0ubuntu1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2020-07-27 at 15:51 +0200, Christophe JAILLET wrote: > Avoid a memset after a call to 'dma_alloc_coherent()'. > This is useless since > commit 518a2f1925c3 ("dma-mapping: zero memory returned from dma_alloc_*") [] > diff --git a/drivers/media/pci/bt8xx/btcx-risc.c b/drivers/media/pci/bt8xx/btcx-risc.c [] > @@ -73,7 +73,6 @@ int btcx_riscmem_alloc(struct pci_dev *pci, > dprintk("btcx: riscmem alloc [%d] dma=%lx cpu=%p size=%d\n", > memcnt, (unsigned long)dma, cpu, size); > } > - memset(risc->cpu,0,risc->size); > return 0; > } Likely NAK. This is not useless as risc->cpu may be reused and the alloc may not have been done.