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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9161C43334 for ; Thu, 16 Jun 2022 09:00:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231703AbiFPJAE (ORCPT ); Thu, 16 Jun 2022 05:00:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230429AbiFPJAD (ORCPT ); Thu, 16 Jun 2022 05:00:03 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 78B872CCA1 for ; Thu, 16 Jun 2022 02:00:02 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 509B512FC; Thu, 16 Jun 2022 02:00:02 -0700 (PDT) Received: from [10.57.82.209] (unknown [10.57.82.209]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4E8203F7F5; Thu, 16 Jun 2022 01:59:59 -0700 (PDT) Message-ID: Date: Thu, 16 Jun 2022 09:59:53 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 Subject: Re: [PATCH v2 2/5] iommu/mediatek: Add error path for loop of mm_dts_parse Content-Language: en-GB To: Yong Wu , Joerg Roedel , Matthias Brugger , Will Deacon Cc: iommu@lists.linux-foundation.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, AngeloGioacchino Del Regno , mingyuan.ma@mediatek.com, yf.wang@mediatek.com, libo.kang@mediatek.com, chengci.xu@mediatek.com, youlin.pei@mediatek.com, anan.sun@mediatek.com, xueqi.zhang@mediatek.com, Guenter Roeck , Dan Carpenter References: <20220616054203.11365-1-yong.wu@mediatek.com> <20220616054203.11365-3-yong.wu@mediatek.com> From: Robin Murphy In-Reply-To: <20220616054203.11365-3-yong.wu@mediatek.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-06-16 06:42, Yong Wu wrote: > The mtk_iommu_mm_dts_parse will parse the smi larbs nodes. if the i+1 > larb is parsed fail(return -EINVAL), we should of_node_put for the 0..i > larbs. In the fail path, one of_node_put matches with of_parse_phandle in > it. > > Fixes: d2e9a1102cfc ("iommu/mediatek: Contain MM IOMMU flow with the MM TYPE") > Signed-off-by: Yong Wu > --- > drivers/iommu/mtk_iommu.c | 21 ++++++++++++++++----- > 1 file changed, 16 insertions(+), 5 deletions(-) > > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c > index 3b2489e8a6dd..ab24078938bf 100644 > --- a/drivers/iommu/mtk_iommu.c > +++ b/drivers/iommu/mtk_iommu.c > @@ -1071,12 +1071,12 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m > > plarbdev = of_find_device_by_node(larbnode); > if (!plarbdev) { > - of_node_put(larbnode); > - return -ENODEV; > + ret = -ENODEV; > + goto err_larbnode_put; > } > if (!plarbdev->dev.driver) { > - of_node_put(larbnode); > - return -EPROBE_DEFER; > + ret = -EPROBE_DEFER; > + goto err_larbnode_put; > } > data->larb_imu[id].dev = &plarbdev->dev; > > @@ -1107,9 +1107,20 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m > DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME); > if (!link) { > dev_err(dev, "Unable to link %s.\n", dev_name(data->smicomm_dev)); > - return -EINVAL; > + ret = -EINVAL; > + goto err_larbnode_put; > } > return 0; > + > +err_larbnode_put: > + while (i--) { > + larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i); > + if (larbnode && of_device_is_available(larbnode)) { > + of_node_put(larbnode); > + of_node_put(larbnode); > + } This looks a bit awkward - could we not just iterate through data->larb_imu and put dev->of_node for each valid dev? Also, of_find_device_by_node() takes a reference on the struct device itself, so strictly we should be doing put_device() on those as well if we're bailing out. Robin. > + } > + return ret; > } > > static int mtk_iommu_probe(struct platform_device *pdev)