From mboxrd@z Thu Jan  1 00:00:00 1970
From: CK Hu <ck.hu@mediatek.com>
Subject: Re: [PATCH 1/7] drm/mediatek: fix possible object reference leak
Date: Tue, 9 Apr 2019 13:15:59 +0800
Message-ID: <1554786959.336.1.camel@mtksdaap41>
References: <1554307455-40361-1-git-send-email-wen.yang99@zte.com.cn>
 <1554307455-40361-2-git-send-email-wen.yang99@zte.com.cn>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org>
In-Reply-To: <1554307455-40361-2-git-send-email-wen.yang99@zte.com.cn>
List-Unsubscribe: <http://lists.infradead.org/mailman/options/linux-arm-kernel>,
 <mailto:linux-arm-kernel-request@lists.infradead.org?subject=unsubscribe>
List-Archive: <http://lists.infradead.org/pipermail/linux-arm-kernel/>
List-Post: <mailto:linux-arm-kernel@lists.infradead.org>
List-Help: <mailto:linux-arm-kernel-request@lists.infradead.org?subject=help>
List-Subscribe: <http://lists.infradead.org/mailman/listinfo/linux-arm-kernel>,
 <mailto:linux-arm-kernel-request@lists.infradead.org?subject=subscribe>
Sender: "linux-arm-kernel" <linux-arm-kernel-bounces@lists.infradead.org>
Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org
To: Wen Yang <wen.yang99@zte.com.cn>
Cc: wang.yi59@zte.com.cn, Philipp Zabel <p.zabel@pengutronix.de>, David Airlie <airlied@linux.ie>, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, Daniel Vetter <daniel@ffwll.ch>, Matthias Brugger <matthias.bgg@gmail.com>, linux-arm-kernel@lists.infradead.org
List-Id: linux-mediatek@lists.infradead.org

Hi, Wen:

On Thu, 2019-04-04 at 00:04 +0800, Wen Yang wrote:
> The call to of_parse_phandle returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
> 
> Detected by coccinelle with the following warnings:
> drivers/gpu/drm/mediatek/mtk_hdmi.c:1521:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 1509, but without a corresponding object release within this function.
> drivers/gpu/drm/mediatek/mtk_hdmi.c:1524:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 1509, but without a corresponding object release within this function.

For this patch, applied to mediatek-drm-fixes-5.1 [1], thanks.

[1]
https://github.com/ckhu-mediatek/linux.git-tags/commits/mediatek-drm-fixes-5.1

Regards,
CK

> 
> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: CK Hu <ck.hu@mediatek.com>
> Cc: Philipp Zabel <p.zabel@pengutronix.de>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Matthias Brugger <matthias.bgg@gmail.com>
> Cc: dri-devel@lists.freedesktop.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-mediatek@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  drivers/gpu/drm/mediatek/mtk_hdmi.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> index 915cc84..ed10f4d 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> @@ -1516,6 +1516,7 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>  	of_node_put(remote);
>  
>  	hdmi->ddc_adpt = of_find_i2c_adapter_by_node(i2c_np);
> +	of_node_put(i2c_np);
>  	if (!hdmi->ddc_adpt) {
>  		dev_err(dev, "Failed to get ddc i2c adapter by node\n");
>  		return -EINVAL;