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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 149A6C43A1D for ; Thu, 12 Jul 2018 08:55:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C073A2086E for ; Thu, 12 Jul 2018 08:55:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C073A2086E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727002AbeGLJDo (ORCPT ); Thu, 12 Jul 2018 05:03:44 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:55894 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726366AbeGLJDo (ORCPT ); Thu, 12 Jul 2018 05:03:44 -0400 Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 910F1D02; Thu, 12 Jul 2018 08:55:05 +0000 (UTC) Date: Thu, 12 Jul 2018 10:55:01 +0200 From: Greg KH To: Benjamin Gaignard , "Rafael J. Wysocki" Cc: broonie@kernel.org, p.paillet@st.com, linux-kernel@vger.kernel.org, m.szyprowski@samsung.com, Benjamin Gaignard Subject: Re: [PATCH] base: core: Remove WARN_ON from link dependencies check Message-ID: <20180712085501.GA25313@kroah.com> References: <20180712080623.21203-1-benjamin.gaignard@st.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180712080623.21203-1-benjamin.gaignard@st.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 12, 2018 at 10:06:23AM +0200, Benjamin Gaignard wrote: > In some cases the link between between customer and supplier > already exist. Do not warn about already existing dependencies > because device_link_add() take care of this case. Why would a link already exist that is asked to be created again? What code path causes this? > > Reported-by: Marek Szyprowski > Signed-off-by: Benjamin Gaignard > --- > drivers/base/core.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/base/core.c b/drivers/base/core.c > index df3e1a44707a..fcdc17f0f349 100644 > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -105,7 +105,7 @@ static int device_is_dependent(struct device *dev, void *target) > struct device_link *link; > int ret; > > - if (WARN_ON(dev == target)) > + if (dev == target) > return 1; > > ret = device_for_each_child(dev, target, device_is_dependent); > @@ -113,7 +113,7 @@ static int device_is_dependent(struct device *dev, void *target) > return ret; > > list_for_each_entry(link, &dev->links.consumers, s_node) { > - if (WARN_ON(link->consumer == target)) > + if (link->consumer == target) > return 1; Both of these WARN_ON are for valid code? That feels really odd to me, I need more explanation here please. thanks, greg k-h