From: Julia Lawall <julia.law...@lip6.fr> 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.
The problem of a free after a devm_request_irq was found using the following semantic match (http://coccinelle.lip6.fr/) // <smpl> @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 ...; } // </smpl> Signed-off-by: Julia Lawall <julia.law...@lip6.fr> --- drivers/media/video/mx2_emmaprp.c | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) diff --git a/drivers/media/video/mx2_emmaprp.c b/drivers/media/video/mx2_emmaprp.c index 5f8a6f5..78c5dc9 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); @@ -922,12 +920,7 @@ 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)); + pcdev->base_emma = devm_request_and_ioremap(&pdev->dev, res_emma); if (!pcdev->base_emma) goto rel_vdev; @@ -969,10 +962,6 @@ 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 +976,6 @@ 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; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
