Re: [PATCH v7 2/3] remoteproc: imx_rpoc: use memory-region-names to avoid hidden ABI

[Mathieu Poirier <mathieu.poirier@linaro.org>]

On Tue, Oct 20, 2026 at 12:50:22PM -0400, Frank.Li@oss.nxp.com wrote:
> From: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
> 
> The driver currently derives the memory region type from the referenced
> memory node name, creating a hidden DT ABI. Since memory node names are
> not constrained by the binding, incorrect names can silently pass DT
> validation, as seen in examples using "vdevbuffer" instead of
> "vdev0buffer" ([1] and [2]).
> 
> Parse memory-region-names to identify the expected memory regions and avoid
> relying on memory node names as ABI.
> 
> Link: https://lore.kernel.org/imx/a3602ef8-2b77-4cc3-adef-2c4cba08a5d9@nabladev.com/ [1]
> Link: https://lore.kernel.org/imx/alexXTYQHUs76J7v@SMW015318/T/#mb9dc709ff3adc24d9db6d30c973f37b580f6f1f9 [2]
> 
> Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
> Reviewed-by: Peng Fan <peng.fan@nxp.com>
> Reviewed-by: Francesco Valla <francesco@valla.it>
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/remoteproc/imx_rproc.c | 32 ++++++++++++++++++++++++++++++--
>  1 file changed, 30 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
> index 581bb07f5893f..1647726893d1a 100644
> --- a/drivers/remoteproc/imx_rproc.c
> +++ b/drivers/remoteproc/imx_rproc.c
> @@ -635,6 +635,25 @@ static int imx_rproc_sm_lmm_prepare(struct rproc *rproc)
>  	return 0;
>  }
>  
> +static int imx_rproc_rmem_to_resource(struct device_node *np,
> +				      int index,
> +				      struct resource *res)
> +{
> +	int ret;
> +
> +	ret = of_reserved_mem_region_to_resource(np, index, res);
> +	if (ret)
> +		return ret;
> +
> +	/* "memory-region-names" is optional */
> +	ret = of_property_read_string_index(np, "memory-region-names",
> +					    index, &res->name);
> +	if (ret == -EINVAL)
> +		return 0;
> +
> +	return ret;
> +}
> +
>  static int imx_rproc_prepare(struct rproc *rproc)
>  {
>  	struct imx_rproc *priv = rproc->priv;
> @@ -648,7 +667,7 @@ static int imx_rproc_prepare(struct rproc *rproc)
>  		int err;
>  		struct resource res;
>  
> -		err = of_reserved_mem_region_to_resource(np, i++, &res);
> +		err = imx_rproc_rmem_to_resource(np, i++, &res);
>  		if (err)
>  			break;
>  
> @@ -823,11 +842,20 @@ static int imx_rproc_addr_init(struct imx_rproc *priv,
>  	if (nph <= 0)
>  		return 0;
>  
> +	if (!of_property_present(np, "memory-region-names")) {
> +		dev_warn(dev, "using node names for carveouts should be avoided\n");

Get rid of dev_warn().

> +	} else {
> +		if (nph != of_property_count_strings(np, "memory-region-names")) {
> +			dev_err(dev, "invalid reserved memory name count\n");
> +			return -EINVAL;
> +		}
> +	}
> +
>  	/* remap optional addresses */
>  	for (a = 0; a < nph; a++) {
>  		struct resource res;
>  
> -		err = of_reserved_mem_region_to_resource(np, a, &res);
> +		err = imx_rproc_rmem_to_resource(np, a, &res);
>  		if (err) {
>  			dev_err(dev, "unable to resolve memory region\n");
>  			return err;
> 
> -- 
> 2.43.0
>