[PATCH] ARM: zImage: atags_to_fdt: Fix node names on added root nodes

[Chris Packham]

On 26/01/21 3:39 pm, Rob Herring wrote:
> Commit 7536c7e03e74 ("of/fdt: Remove redundant kbasename function
> call") exposed a bug creating DT nodes in the ATAGS to DT fixup code.
> Non-existent nodes would mistaken get created with a leading '/'. The
> problem was fdt_path_offset() takes a full path while creating a node
> with fdt_add_subnode() takes just the basename.
>
> Since this we only add root child nodes, we can just skip over the '/'.
>
> Fixes: 7536c7e03e74 ("of/fdt: Remove redundant kbasename function call")
> Reported-by: Chris Packham <chris.packham at alliedtelesis.co.nz>
> Cc: Qi Zheng <arch0.zheng at gmail.com>
> Cc: Russell King <linux at armlinux.org.uk>
> Signed-off-by: Rob Herring <robh at kernel.org>

Thanks Rob,

Tested-by: Chris Packham <chris.packham at alliedtelesis.co.nz>
> ---
>   arch/arm/boot/compressed/atags_to_fdt.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/compressed/atags_to_fdt.c b/arch/arm/boot/compressed/atags_to_fdt.c
> index 8452753efebe..31927d2fe297 100644
> --- a/arch/arm/boot/compressed/atags_to_fdt.c
> +++ b/arch/arm/boot/compressed/atags_to_fdt.c
> @@ -15,7 +15,8 @@ static int node_offset(void *fdt, const char *node_path)
>   {
>   	int offset = fdt_path_offset(fdt, node_path);
>   	if (offset == -FDT_ERR_NOTFOUND)
> -		offset = fdt_add_subnode(fdt, 0, node_path);
> +		/* Add the node to root if not found, dropping the leading '/' */
> +		offset = fdt_add_subnode(fdt, 0, node_path + 1);
>   	return offset;
>   }
>