Re: [PATCH 04/23] interconnect: imx: fix registration race

[Konrad Dybcio]

On 1.02.2023 11:15, Johan Hovold wrote:
> The current interconnect provider registration interface is inherently
> racy as nodes are not added until the after adding the provider. This
> can specifically cause racing DT lookups to fail.
> 
> Switch to using the new API where the provider is not registered until
> after it has been fully initialised.
> 
> Fixes: f0d8048525d7 ("interconnect: Add imx core driver")
> Cc: stable@xxxxxxxxxxxxxxx      # 5.8
> Cc: Leonard Crestez <leonard.crestez@xxxxxxx>
> Cc: Alexandre Bailon <abailon@xxxxxxxxxxxx>
> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
> ---
Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>

Konrad
>  drivers/interconnect/imx/imx.c | 20 ++++++++++----------
>  1 file changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/interconnect/imx/imx.c b/drivers/interconnect/imx/imx.c
> index 823d9be9771a..979ed610f704 100644
> --- a/drivers/interconnect/imx/imx.c
> +++ b/drivers/interconnect/imx/imx.c
> @@ -295,6 +295,9 @@ int imx_icc_register(struct platform_device *pdev,
>  	provider->xlate = of_icc_xlate_onecell;
>  	provider->data = data;
>  	provider->dev = dev->parent;
> +
> +	icc_provider_init(provider);
> +
>  	platform_set_drvdata(pdev, imx_provider);
>  
>  	if (settings) {
> @@ -306,20 +309,18 @@ int imx_icc_register(struct platform_device *pdev,
>  		}
>  	}
>  
> -	ret = icc_provider_add(provider);
> -	if (ret) {
> -		dev_err(dev, "error adding interconnect provider: %d\n", ret);
> +	ret = imx_icc_register_nodes(imx_provider, nodes, nodes_count, settings);
> +	if (ret)
>  		return ret;
> -	}
>  
> -	ret = imx_icc_register_nodes(imx_provider, nodes, nodes_count, settings);
> +	ret = icc_provider_register(provider);
>  	if (ret)
> -		goto provider_del;
> +		goto err_unregister_nodes;
>  
>  	return 0;
>  
> -provider_del:
> -	icc_provider_del(provider);
> +err_unregister_nodes:
> +	imx_icc_unregister_nodes(&imx_provider->provider);
>  	return ret;
>  }
>  EXPORT_SYMBOL_GPL(imx_icc_register);
> @@ -328,9 +329,8 @@ void imx_icc_unregister(struct platform_device *pdev)
>  {
>  	struct imx_icc_provider *imx_provider = platform_get_drvdata(pdev);
>  
> +	icc_provider_deregister(&imx_provider->provider);
>  	imx_icc_unregister_nodes(&imx_provider->provider);
> -
> -	icc_provider_del(&imx_provider->provider);
>  }
>  EXPORT_SYMBOL_GPL(imx_icc_unregister);
>