From patchwork Fri Aug 10 13:59:11 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julia Lawall X-Patchwork-Id: 1305701 Return-Path: X-Original-To: patchwork-linux-media@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 6D0573FC66 for ; Fri, 10 Aug 2012 13:59:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756850Ab2HJN7Q (ORCPT ); Fri, 10 Aug 2012 09:59:16 -0400 Received: from mail4-relais-sop.national.inria.fr ([192.134.164.105]:39616 "EHLO mail4-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754871Ab2HJN7P (ORCPT ); Fri, 10 Aug 2012 09:59:15 -0400 X-IronPort-AV: E=Sophos;i="4.77,745,1336341600"; d="scan'208";a="152838601" Received: from technetium.rsr.lip6.fr ([132.227.76.37]) by mail4-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-SHA; 10 Aug 2012 15:59:12 +0200 Date: Fri, 10 Aug 2012 15:59:11 +0200 (CEST) From: Julia Lawall X-X-Sender: jll@hadrien To: Lars-Peter Clausen cc: Dan Carpenter , Mauro Carvalho Chehab , kernel-janitors@vger.kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drivers/media/video/mx2_emmaprp.c: use devm_kzalloc and devm_clk_get In-Reply-To: <501FD69D.7070702@metafoo.de> Message-ID: References: <1344104607-18805-1-git-send-email-Julia.Lawall@lip6.fr> <20120806142323.GO4352@mwanda> <20120806142650.GT4403@mwanda> <501FD69D.7070702@metafoo.de> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Julia Lawall Using devm_kzalloc and devm_clk_get simplifies the code and ensures that the use of devm_request_irq is safe. When kzalloc and kfree were used, the interrupt could be triggered after the handler's data argument had been freed. Add missing return code initializations in the error handling code for devm_request_and_ioremap and devm_request_irq. The problem of a free after a devm_request_irq was found using the following semantic match (http://coccinelle.lip6.fr/) // @r exists@ expression e1,e2,x,a,b,c,d; identifier free; position p1,p2; @@ devm_request_irq@p1(e1,e2,...,x) ... when any when != e2 = a when != x = b if (...) { ... when != e2 = c when != x = d free@p2(...,x,...); ... return ...; } // Signed-off-by: Julia Lawall --- v2: patch updated to add nearby ret initializations. Please let me know if some other constants should be returned on the failure of devm_request_and_ioremap and devm_request_irq. drivers/media/video/mx2_emmaprp.c | 33 ++++++++++++--------------------- 1 file changed, 12 insertions(+), 21 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/media/video/mx2_emmaprp.c b/drivers/media/video/mx2_emmaprp.c index 5f8a6f5..9fe9ec6 100644 --- a/drivers/media/video/mx2_emmaprp.c +++ b/drivers/media/video/mx2_emmaprp.c @@ -874,29 +874,27 @@ static int emmaprp_probe(struct platform_device *pdev) int irq_emma; int ret; - pcdev = kzalloc(sizeof *pcdev, GFP_KERNEL); + pcdev = devm_kzalloc(&pdev->dev, sizeof(*pcdev), GFP_KERNEL); if (!pcdev) return -ENOMEM; spin_lock_init(&pcdev->irqlock); - pcdev->clk_emma = clk_get(&pdev->dev, NULL); + pcdev->clk_emma = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(pcdev->clk_emma)) { - ret = PTR_ERR(pcdev->clk_emma); - goto free_dev; + return PTR_ERR(pcdev->clk_emma); } irq_emma = platform_get_irq(pdev, 0); res_emma = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (irq_emma < 0 || res_emma == NULL) { dev_err(&pdev->dev, "Missing platform resources data\n"); - ret = -ENODEV; - goto free_clk; + return -ENODEV; } ret = v4l2_device_register(&pdev->dev, &pcdev->v4l2_dev); if (ret) - goto free_clk; + return ret; mutex_init(&pcdev->dev_mutex); @@ -922,21 +920,20 @@ static int emmaprp_probe(struct platform_device *pdev) platform_set_drvdata(pdev, pcdev); - if (devm_request_mem_region(&pdev->dev, res_emma->start, - resource_size(res_emma), MEM2MEM_NAME) == NULL) - goto rel_vdev; - - pcdev->base_emma = devm_ioremap(&pdev->dev, res_emma->start, - resource_size(res_emma)); - if (!pcdev->base_emma) + pcdev->base_emma = devm_request_and_ioremap(&pdev->dev, res_emma); + if (!pcdev->base_emma) { + ret = -ENXIO; goto rel_vdev; + } pcdev->irq_emma = irq_emma; pcdev->res_emma = res_emma; if (devm_request_irq(&pdev->dev, pcdev->irq_emma, emmaprp_irq, - 0, MEM2MEM_NAME, pcdev) < 0) + 0, MEM2MEM_NAME, pcdev) < 0) { + ret = -ENODEV; goto rel_vdev; + } pcdev->alloc_ctx = vb2_dma_contig_init_ctx(&pdev->dev); if (IS_ERR(pcdev->alloc_ctx)) { @@ -969,10 +966,6 @@ rel_vdev: video_device_release(vfd); unreg_dev: v4l2_device_unregister(&pcdev->v4l2_dev); -free_clk: - clk_put(pcdev->clk_emma); -free_dev: - kfree(pcdev); return ret; } @@ -987,8 +980,6 @@ static int emmaprp_remove(struct platform_device *pdev) v4l2_m2m_release(pcdev->m2m_dev); vb2_dma_contig_cleanup_ctx(pcdev->alloc_ctx); v4l2_device_unregister(&pcdev->v4l2_dev); - clk_put(pcdev->clk_emma); - kfree(pcdev); return 0; }