Re: [PATCH] fix: drm/mediatek: mtk_drm_probe: of_node_get in loop overwrites previous node references without release

[WenTao Liang]

> 2026年6月26日 21:28，WenTao Liang <vulab@xxxxxxxxxxx> 写道：
> 
> In the for_each_child_of_node loop, private->comp_node[comp_id] and
>  private->mutex_node are assigned via of_node_get without first releasing
>  any previously stored reference for the same index. When the same comp_id
>  or mmsys_id matches multiple nodes, earlier node references are
>  overwritten and permanently leaked.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 1ef7ed48356c ("drm/mediatek: Modify mediatek-drm for mt8195 multi mmsys support")
> Signed-off-by: WenTao Liang <vulab@xxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_drv.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> index c86a3f54f35b..2c0d8db9ade2 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> @@ -1138,6 +1138,7 @@ static int mtk_drm_probe(struct platform_device *pdev)
> 
> 			id = of_alias_get_id(node, "mutex");
> 			if (id < 0 || id == private->data->mmsys_id) {
> +				of_node_put(private->mutex_node);
> 				private->mutex_node = of_node_get(node);
> 				dev_dbg(dev, "get mutex for mmsys %d", private->data->mmsys_id);
> 			}
> @@ -1153,7 +1154,7 @@ static int mtk_drm_probe(struct platform_device *pdev)
> 
> 		if (!mtk_drm_find_mmsys_comp(private, comp_id))
> 			continue;
> -
> +		of_node_put(private->comp_node[comp_id]);
> 		private->comp_node[comp_id] = of_node_get(node);
> 
> 		/*
> -- 
> 2.39.5 (Apple Git-154)

Please ignore this patch. I will resend a proper version after
learning the kernel submission process.

Apologies for the noise.

Best regards,
WenTao Liang