Re: [PATCH v3 1/3] of: Move simple-framebuffer device handling from simplefb to of

[Javier Martinez Canillas]

Hello Hector,

On Sun, Dec 12, 2021 at 7:24 AM Hector Martin <marcan@xxxxxxxxx> wrote:
>
> This code is required for both simplefb and simpledrm, so let's move it
> into the OF core instead of having it as an ad-hoc initcall in the
> drivers.
>
> Acked-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
> Signed-off-by: Hector Martin <marcan@xxxxxxxxx>
> ---
>  drivers/of/platform.c          |  4 ++++
>  drivers/video/fbdev/simplefb.c | 21 +--------------------
>  2 files changed, 5 insertions(+), 20 deletions(-)
>

This is indeed a much better approach than what I suggested. I just
have one comment.

> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index b3faf89744aa..793350028906 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -540,6 +540,10 @@ static int __init of_platform_default_populate_init(void)
>                 of_node_put(node);
>         }
>
> +       node = of_get_compatible_child(of_chosen, "simple-framebuffer");

You have to check if the node variable is NULL here.

> +       of_platform_device_create(node, NULL, NULL);

Otherwise this could lead to a NULL pointer dereference if debug
output is enabled (the node->full_name is printed).

Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>

Best regards,
Javier