[PATCH] drm/mediatek: fix null pointer dereference
From: CK Hu <hidden>
Date: 2016-10-28 08:35:01
Also in:
dri-devel, linux-mediatek, lkml
Hi, Matthias: Even though OVL HW would not be enabled before component_add() in current design, your patch would be safe for any situation. Acked-by CK Hu [off-list ref] Regards, CK On Wed, 2016-10-26 at 16:09 +0200, Matthias Brugger wrote:
quoted hunk
The probe function requests the interrupt before initializing the ddp component. Which leads to a null pointer dereference at boot. Fix this by requesting the interrput after all components got initialized properly. Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.") Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com> --- drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c index 019b7ca..1e78159 100644 --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c@@ -250,13 +250,6 @@ static int mtk_disp_ovl_probe(struct platform_device *pdev) if (irq < 0) return irq; - ret = devm_request_irq(dev, irq, mtk_disp_ovl_irq_handler, - IRQF_TRIGGER_NONE, dev_name(dev), priv); - if (ret < 0) { - dev_err(dev, "Failed to request irq %d: %d\n", irq, ret); - return ret; - } - comp_id = mtk_ddp_comp_get_id(dev->of_node, MTK_DISP_OVL); if (comp_id < 0) { dev_err(dev, "Failed to identify by alias: %d\n", comp_id);@@ -272,6 +265,13 @@ static int mtk_disp_ovl_probe(struct platform_device *pdev) platform_set_drvdata(pdev, priv); + ret = devm_request_irq(dev, irq, mtk_disp_ovl_irq_handler, + IRQF_TRIGGER_NONE, dev_name(dev), priv); + if (ret < 0) { + dev_err(dev, "Failed to request irq %d: %d\n", irq, ret); + return ret; + } + ret = component_add(dev, &mtk_disp_ovl_component_ops); if (ret) dev_err(dev, "Failed to add component: %d\n", ret);