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=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,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 3C705C43441 for ; Fri, 16 Nov 2018 11:51:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0FBA92087A for ; Fri, 16 Nov 2018 11:51:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0FBA92087A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-pci-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389587AbeKPWDi (ORCPT ); Fri, 16 Nov 2018 17:03:38 -0500 Received: from foss.arm.com ([217.140.101.70]:50216 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727963AbeKPWDi (ORCPT ); Fri, 16 Nov 2018 17:03:38 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 44D5B80D; Fri, 16 Nov 2018 03:51:36 -0800 (PST) Received: from e107981-ln.cambridge.arm.com (e107981-ln.cambridge.arm.com [10.1.197.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BF3743F718; Fri, 16 Nov 2018 03:51:34 -0800 (PST) Date: Fri, 16 Nov 2018 11:51:29 +0000 From: Lorenzo Pieralisi To: Ladislav Michl , Wei Yongjun Cc: Bjorn Helgaas , Kishon Vijay Abraham I , Bjorn Helgaas , linux-omap@vger.kernel.org, linux-pci@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH -next] PCI: dra7xx: Fix potential NULL dereference Message-ID: <20181116115129.GA3228@e107981-ln.cambridge.arm.com> References: <1516284037-81537-1-git-send-email-weiyongjun1@huawei.com> <20180118145420.GA21163@lenoch> <20180118183525.GG53542@bhelgaas-glaptop.roam.corp.google.com> <20180119095857.GA26765@lenoch> <20180119170657.GA27882@lenoch> <20180120001645.GA21343@lenoch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180120001645.GA21343@lenoch> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Sat, Jan 20, 2018 at 01:16:45AM +0100, Ladislav Michl wrote: > On Fri, Jan 19, 2018 at 06:06:57PM +0100, Ladislav Michl wrote: > > On Fri, Jan 19, 2018 at 10:58:57AM +0100, Ladislav Michl wrote: > > > On Thu, Jan 18, 2018 at 12:35:25PM -0600, Bjorn Helgaas wrote: > > > > That's probably a better idea. Maybe we should add a comment like this > > > > to help avoid this in the future: > > > > > > That seems to spot another a bit more serious problem (given how late > > > release cycle is now). > > > > > > Both devm_ioremap() and devm_ioremap_resource() shares the same release > > > function: devm_ioremap_release(). However this function is not aware of > > > memory region previously requested by devm_request_mem_region() called > > > from devm_ioremap_resource(). > > > > > > Bellow is just a quick hack, even untested as looking at devm_ioremap, > > > devm_ioremap_wc and devm_ioremap_wc, there is some room for optimization. > > > > Okay, forget it, above analysis is not correct, however there is a bug (and > > also in PCI version). To show it, let's make following modification: > > I will never ever work in single tree for two different boards without full > recompile (which should save time and caused opposite) as it makes debugging > pointless - there is no bug. > > As a request forgiveness, please accept following draft as proposed solution > for $subj Wei, Ladislav, getting back to this old thread, I would mark it as "changes requested" and expect someone to post a follow-up patch, I do not think this is a solved problem. Lorenzo > Subject: [PATCH] PCI: dra7xx: Use devm_ioremap_resource() > > diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c > index 8bf7c2714db6..7f422ae258ac 100644 > --- a/drivers/pci/dwc/pci-dra7xx.c > +++ b/drivers/pci/dwc/pci-dra7xx.c > @@ -409,14 +409,14 @@ static int __init dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx, > ep->ops = &pcie_ep_ops; > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics"); > - pci->dbi_base = devm_ioremap(dev, res->start, resource_size(res)); > - if (!pci->dbi_base) > - return -ENOMEM; > + pci->dbi_base = devm_ioremap_resource(dev, res); > + if (IS_ERR(pci->dbi_base)) > + return PTR_ERR(pci->dbi_base); > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics2"); > - pci->dbi_base2 = devm_ioremap(dev, res->start, resource_size(res)); > - if (!pci->dbi_base2) > - return -ENOMEM; > + pci->dbi_base2 = devm_ioremap_resource(dev, res); > + if (IS_ERR(pci->dbi_base2)) > + return PTR_ERR(pci->dbi_base2); > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space"); > if (!res)