2022-09-14 00:00:15

by Abhinav Kumar

[permalink] [raw]
Subject: Re: [Freedreno] [PATCH] drm/msm: Fix return type of mdp4_lvds_connector_mode_valid

Hi Nathan

Thanks for the patch.

On 9/13/2022 1:55 PM, Nathan Huckleberry wrote:
> The mode_valid field in drm_connector_helper_funcs is expected to be of
> type:
> enum drm_mode_status (* mode_valid) (struct drm_connector *connector,
> struct drm_display_mode *mode);
>
> The mismatched return type breaks forward edge kCFI since the underlying
> function definition does not match the function hook definition.
>
> The return type of mdp4_lvds_connector_mode_valid should be changed from
> int to enum drm_mode_status.
>
> Reported-by: Dan Carpenter <[email protected]>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1703
> Cc: [email protected]
> Signed-off-by: Nathan Huckleberry <[email protected]>

From what I can see this one has been this way since lvds support was
added. Hence this should have

Fixes: 3e87599b68e7 ("drm/msm/mdp4: add LVDS panel support")

Reviewed-by: Abhinav Kumar <[email protected]>
> ---
> drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
> index 7288041dd86a..7444b75c4215 100644
> --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
> +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c
> @@ -56,8 +56,9 @@ static int mdp4_lvds_connector_get_modes(struct drm_connector *connector)
> return ret;
> }
>
> -static int mdp4_lvds_connector_mode_valid(struct drm_connector *connector,
> - struct drm_display_mode *mode)
> +static enum drm_mode_status
> +mdp4_lvds_connector_mode_valid(struct drm_connector *connector,
> + struct drm_display_mode *mode)
> {
> struct mdp4_lvds_connector *mdp4_lvds_connector =
> to_mdp4_lvds_connector(connector);