Re: [Intel-gfx] [PATCH 18/22] drm/i915: Use drm_mode_init() for on-stack modes

[Jani Nikula <jani.nikula@linux.intel.com>]

On Fri, 18 Feb 2022, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Initialize on-stack modes with drm_mode_init() to guarantee
> no stack garbage in the list head, or that we aren't copying
> over another mode's list head.
>
> Based on the following cocci script, with manual fixups:
> @decl@
> identifier M;
> expression E;
> @@
> - struct drm_display_mode M = E;
> + struct drm_display_mode M;
>
> @@
> identifier decl.M;
> expression decl.E;
> statement S, S1;
> @@
> struct drm_display_mode M;
> ... when != S
> + drm_mode_init(&M, &E);
> +
> S1
>
> @@
> expression decl.E;
> @@
> - &*E
> + E
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

I wonder if that cocci could be added to scripts/coccinelle or something
to detect anyone adding new ones?

Anyway,

Reviewed-by: Jani Nikula <jani.nikula@intel.com>


> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 740620ef07ad..74c5a99ab276 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -6898,8 +6898,9 @@ intel_crtc_update_active_timings(const struct intel_crtc_state *crtc_state)
>  {
>  	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
>  	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> -	struct drm_display_mode adjusted_mode =
> -		crtc_state->hw.adjusted_mode;
> +	struct drm_display_mode adjusted_mode;
> +
> +	drm_mode_init(&adjusted_mode, &crtc_state->hw.adjusted_mode);
>  
>  	if (crtc_state->vrr.enable) {
>  		adjusted_mode.crtc_vtotal = crtc_state->vrr.vmax;

-- 
Jani Nikula, Intel Open Source Graphics Center