From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757203AbaEPLQp (ORCPT ); Fri, 16 May 2014 07:16:45 -0400 Received: from mail-la0-f50.google.com ([209.85.215.50]:53555 "EHLO mail-la0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756806AbaEPLQm (ORCPT ); Fri, 16 May 2014 07:16:42 -0400 Date: Fri, 16 May 2014 13:16:46 +0200 From: Emil Goode To: walter harms Cc: Shawn Guo , Sascha Hauer , Russell King , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH v2] ARM: imx: fix error handling Message-ID: <20140516111646.GC4366@lianli> References: <1400234045-6022-1-git-send-email-emilgoode@gmail.com> <5375EB13.8000200@bfs.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5375EB13.8000200@bfs.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Walter, On Fri, May 16, 2014 at 12:40:19PM +0200, walter harms wrote: > > > Am 16.05.2014 11:54, schrieb Emil Goode: > > If we fail to allocate struct platform_device pdev we > > dereference it after the goto label err. > > > > I have rearranged the error handling a bit to fix the issue > > and also make it more clear. > > > > Signed-off-by: Emil Goode > > --- > > v2: Changed to return -ENOMEM instead of ret where possible and > > updated the subject line. > > > > arch/arm/mach-imx/devices/platform-ipu-core.c | 22 +++++++++++++--------- > > 1 file changed, 13 insertions(+), 9 deletions(-) > > > > diff --git a/arch/arm/mach-imx/devices/platform-ipu-core.c b/arch/arm/mach-imx/devices/platform-ipu-core.c > > index fc4dd7c..68f2a4a 100644 > > --- a/arch/arm/mach-imx/devices/platform-ipu-core.c > > +++ b/arch/arm/mach-imx/devices/platform-ipu-core.c > > @@ -77,34 +77,38 @@ struct platform_device *__init imx_alloc_mx3_camera( > > > > pdev = platform_device_alloc("mx3-camera", 0); > > if (!pdev) > > - goto err; > > + return ERR_PTR(-ENOMEM); > > > > pdev->dev.dma_mask = kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL); > > if (!pdev->dev.dma_mask) > > - goto err; > > + goto put_pdev; > > > > *pdev->dev.dma_mask = DMA_BIT_MASK(32); > > pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32); > > > > ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res)); > > if (ret) > > - goto err; > > + goto free_dma_mask; > > > > if (pdata) { > > struct mx3_camera_pdata *copied_pdata; > > > > ret = platform_device_add_data(pdev, pdata, sizeof(*pdata)); > > - if (ret) { > > -err: > > - kfree(pdev->dev.dma_mask); > > - platform_device_put(pdev); > > - return ERR_PTR(-ENODEV); > > - } > > + if (ret) > > + goto free_dma_mask; > > + > > copied_pdata = dev_get_platdata(&pdev->dev); > > copied_pdata->dma_dev = &imx_ipu_coredev->dev; > > > the patch is fine, but what use is this copied_pdata ? > It scope ends next line ? > > re, > wh I also thought that looked a bit odd, but copied_pdata is a temporary pointer to platform_data of the dev struct. dev_get_platdata looks like this: static inline void *dev_get_platdata(const struct device *dev) { return dev->platform_data; } So I believe it's a more compact way of writing: pdev->dev->platform_data->dma_dev = &imx_ipu_coredev->dev; Best regards, Emil Goode > > > } > > > > return pdev; > > + > > +free_dma_mask: > > + kfree(pdev->dev.dma_mask); > > +put_pdev: > > + platform_device_put(pdev); > > + > > + return ERR_PTR(ret); > > } > > > > struct platform_device *__init imx_add_mx3_sdc_fb(