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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 82C38C35242 for ; Tue, 11 Feb 2020 19:11:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5E2AE21569 for ; Tue, 11 Feb 2020 19:11:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="zondnlkg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728295AbgBKTLz (ORCPT ); Tue, 11 Feb 2020 14:11:55 -0500 Received: from mail-pg1-f193.google.com ([209.85.215.193]:42548 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730444AbgBKTLz (ORCPT ); Tue, 11 Feb 2020 14:11:55 -0500 Received: by mail-pg1-f193.google.com with SMTP id w21so6215451pgl.9 for ; Tue, 11 Feb 2020 11:11:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Tsow3V7Qcg/7TdOBvQfEChXDPTjmm/i/J9UtL8nyGdQ=; b=zondnlkgAJViZhnsfy6H4zqUsOW8TjHRFBApbJIsN0y0H5PHvFZBtsSOT9Dyf41nMe EcNKxiErTEGxr4+pljj1+euUZq2JiO4RMBE0e5jtlkyqkBtF6vNqB8NqQuvqJlpq+DhO TtTo5GEXOEdGRCU/0EASkPR7z2KFC4Pi8Qv5zO0Y+3ago2m5129BIgwmFeW5L3QJGnpe lZDs3OSRPNi5LkPBrwC0NcWsSuv5XOMG7XqtJM+YtZf5PhetIvRU0wtL4V0hWNfwqalI u4rbtVr4HDgiVxjTqAxY7mMLgREOBGlMemylNEP/FR+ZbWASoJvArkUPGpoAcK58PDfz ehBA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Tsow3V7Qcg/7TdOBvQfEChXDPTjmm/i/J9UtL8nyGdQ=; b=ZtkWEyKkyEh/blTdhhx+tpDeQb5O6l3u4nESfrnpEta0Px9xq/kgmky++61rm/wdGv j2vFNUMDkNrxtDsHnIykVzvR6TGkAxH4cBRTGq2Xz3AEmhkQ4G8h8AZ1KUPdIaKS+AfE wuW6kSAICLpLUTs1psTz0ckcrioxVIMB+rgV6b95/p3bJSEu4bkrCRidrHHB0/PJxNbh xoq6rb1MgrqPcL43Yv+HNSMRtO+8FV96R+Szy/K99/4L6KkjKVGxI4q9j4P9UBA18si7 rzeWIjEA/sY1gjzDWHlxSUzoed233nOD+tPnU3K1O3DCXKEySN+B68Y5/hO99zgfsq0S E//g== X-Gm-Message-State: APjAAAXzixKl4Ol++yrnbkmMSG+gJlYzc9krV8NDGUWqTfO7Bw16S9bi R4ijj45u2sgkmSSX336LT4De X-Google-Smtp-Source: APXvYqzhJB7rfJbmXLIaUCiKe6GXen7+4eeBQ7SZcbGsxfwdiyucbZcgMROkcH+xdR59gIUnOiITTw== X-Received: by 2002:a63:f402:: with SMTP id g2mr4174697pgi.405.1581448314841; Tue, 11 Feb 2020 11:11:54 -0800 (PST) Received: from Mani-XPS-13-9360 ([2409:4072:638b:7653:754d:196d:c455:1f88]) by smtp.gmail.com with ESMTPSA id d24sm5327630pfq.75.2020.02.11.11.11.50 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 11 Feb 2020 11:11:54 -0800 (PST) Date: Wed, 12 Feb 2020 00:41:47 +0530 From: Manivannan Sadhasivam To: Greg KH Cc: arnd@arndb.de, smohanad@codeaurora.org, jhugo@codeaurora.org, kvalo@codeaurora.org, bjorn.andersson@linaro.org, hemantk@codeaurora.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 02/16] bus: mhi: core: Add support for registering MHI controllers Message-ID: <20200211191147.GB11908@Mani-XPS-13-9360> References: <20200131135009.31477-1-manivannan.sadhasivam@linaro.org> <20200131135009.31477-3-manivannan.sadhasivam@linaro.org> <20200206165606.GA3894455@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200206165606.GA3894455@kroah.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi Greg, On Thu, Feb 06, 2020 at 05:56:06PM +0100, Greg KH wrote: > On Fri, Jan 31, 2020 at 07:19:55PM +0530, Manivannan Sadhasivam wrote: > > +static void mhi_release_device(struct device *dev) > > +{ > > + struct mhi_device *mhi_dev = to_mhi_device(dev); > > + > > + if (mhi_dev->ul_chan) > > + mhi_dev->ul_chan->mhi_dev = NULL; > > That looks really odd. Why didn't you just drop the reference you > should have grabbed here for this pointer? You did properly increment > it when you saved it, right? :) > Well, there is no reference count (kref) exist for mhi_dev. And we really needed to NULL the mhi_dev to avoid any dangling reference to it. The reason for not having kref is that, each mhi_dev will be used by maximum of 2 channels only. So thought that refcounting is not needed. Please correct me if I'm wrong. Thanks, Mani > > + > > + if (mhi_dev->dl_chan) > > + mhi_dev->dl_chan->mhi_dev = NULL; > > Same here. > > thanks, > > greg k-h