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=-11.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 E47FAC433E2 for ; Sun, 19 Jul 2020 14:02:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C28F62080D for ; Sun, 19 Jul 2020 14:02:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LYPxtBd3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726419AbgGSOCA (ORCPT ); Sun, 19 Jul 2020 10:02:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725988AbgGSOB7 (ORCPT ); Sun, 19 Jul 2020 10:01:59 -0400 Received: from mail-pl1-x644.google.com (mail-pl1-x644.google.com [IPv6:2607:f8b0:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB452C0619D2; Sun, 19 Jul 2020 07:01:59 -0700 (PDT) Received: by mail-pl1-x644.google.com with SMTP id q17so7474156pls.9; Sun, 19 Jul 2020 07:01:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Rv9i5ahW69IEp+AW3DUIhCv4FyNoa8w7LHOfx/9zJxU=; b=LYPxtBd3qJoC6tdkkeBgVXRR0MazvfOrwthfLhmeVv71eYROEcVxeqePT3Y/MNxODS d33bSSUrQjCGCNs7x5vKrXVr2DEAJ8BzNpdEdYjPu52WfqiMR2l6Vq2TilnSiAB+5o0W bTnA7SD3Eu8Gb6AmmtcYyUsb1TfoZrOG1cogzKvO1p+NorlgLYuc1agYjDhKUAkMvEgr GHE5u+YCTdfcb92t0Fu6sUJhjcfdXj74msG+LzBaXjmI/RsUjoHozyZwmCS/lqN9gX+e GPgyH9OBbT5TJ57i0zecurPyUMNqy5sdwZiveGaHUzWGPatxLFJNXXrDRACNTRlw6jbq MlUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=Rv9i5ahW69IEp+AW3DUIhCv4FyNoa8w7LHOfx/9zJxU=; b=FgAW0NDzumJ0HRs9s7SeG9rueHQ86isnn58nxf+SpdYnLPaAPz7Bfwwhdb/kQAvdiP dp8KPCkkL7oMnGR5YvAXLxHODaf7CbOGmn6tfM4ohhUCECMYqo4goawYwomR07GAQydH ynwzis9RHJGu7M9o3J/524NN2ZkBE05Raml12aojB5BY8O00DdOVq+DPHes7UHP5rwpQ soTXHgmrsnvbwyTva73l+061Sdm/dXPT6XGABizOVMjsLhVDdupkVied0DG/Zfwa/EiX cMaZC2rAZijEKSTPbxvlov07GcSKqI9Pew4p41VgMmFObt7JbyKDISshP9HxebcCdMga OROQ== X-Gm-Message-State: AOAM533PfvtCzQL1IrbV/Lhasn7MJndpEswJR7Hfrwq9Uf2OHnJr8J2H wNaQziRgMIudJisA9x3l/04= X-Google-Smtp-Source: ABdhPJwDuV/wp/oBfRYX2FG8lmogMmZW6aqTpG5zeAf2vm+WYRSunkaXpgGdzj25Q6ZMwquYNjAGFA== X-Received: by 2002:a17:90a:f206:: with SMTP id bs6mr18967894pjb.48.1595167319453; Sun, 19 Jul 2020 07:01:59 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id o12sm13971349pfu.188.2020.07.19.07.01.58 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sun, 19 Jul 2020 07:01:59 -0700 (PDT) Date: Sun, 19 Jul 2020 07:01:58 -0700 From: Guenter Roeck To: Xu Wang Cc: wim@linux-watchdog.org, linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] watchdog: pcwd_usb: remove needless check before usb_free_coherent() Message-ID: <20200719140158.GA37652@roeck-us.net> References: <20200713055348.21620-1-vulab@iscas.ac.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200713055348.21620-1-vulab@iscas.ac.cn> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 13, 2020 at 05:53:48AM +0000, Xu Wang wrote: > usb_free_coherent() is safe with NULL usb_pcwd->intr_buffer and > this check is not required. > > Signed-off-by: Xu Wang Reviewed-by: Guenter Roeck > --- > drivers/watchdog/pcwd_usb.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/watchdog/pcwd_usb.c b/drivers/watchdog/pcwd_usb.c > index 2f44af1831d0..6726301ac02e 100644 > --- a/drivers/watchdog/pcwd_usb.c > +++ b/drivers/watchdog/pcwd_usb.c > @@ -585,9 +585,8 @@ static struct notifier_block usb_pcwd_notifier = { > static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd) > { > usb_free_urb(usb_pcwd->intr_urb); > - if (usb_pcwd->intr_buffer != NULL) > - usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size, > - usb_pcwd->intr_buffer, usb_pcwd->intr_dma); > + usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size, > + usb_pcwd->intr_buffer, usb_pcwd->intr_dma); > kfree(usb_pcwd); > } >