Re: [PATCH] drm/amd/display: Check all enabled planes in dm_check_crtc_cursor

[Hamza Mahfooz <hamza.mahfooz@amd.com>]

On 9/12/23 06:22, Michel Dänzer wrote:
> From: Michel Dänzer <mdaenzer@redhat.com>
> 
> It was only checking planes which had any state changes in the same
> commit. However, it also needs to check other enabled planes.
> 
> Not doing this meant that a commit might spuriously "succeed", resulting
> in the cursor plane displaying with incorrect scaling. See
> https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3177#note_1824263
> for an example.
> 
> Fixes: d1bfbe8a3202 ("amd/display: check cursor plane matches underlying plane")
> Signed-off-by: Michel Dänzer <mdaenzer@redhat.com>

Applied, thanks!

> ---
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 14 ++++++++++++--
>   1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 88ba8b66de1f..81c9d39567db 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -9836,14 +9836,24 @@ static int dm_check_crtc_cursor(struct drm_atomic_state *state,
>   	 * blending properties match the underlying planes'.
>   	 */
>   
> -	new_cursor_state = drm_atomic_get_new_plane_state(state, cursor);
> -	if (!new_cursor_state || !new_cursor_state->fb)
> +	new_cursor_state = drm_atomic_get_plane_state(state, cursor);
> +	if (IS_ERR(new_cursor_state))
> +		return PTR_ERR(new_cursor_state);
> +
> +	if (!new_cursor_state->fb)
>   		return 0;
>   
>   	dm_get_oriented_plane_size(new_cursor_state, &cursor_src_w, &cursor_src_h);
>   	cursor_scale_w = new_cursor_state->crtc_w * 1000 / cursor_src_w;
>   	cursor_scale_h = new_cursor_state->crtc_h * 1000 / cursor_src_h;
>   
> +	/* Need to check all enabled planes, even if this commit doesn't change
> +	 * their state
> +	 */
> +	i = drm_atomic_add_affected_planes(state, crtc);
> +	if (i)
> +		return i;
> +
>   	for_each_new_plane_in_state_reverse(state, underlying, new_underlying_state, i) {
>   		/* Narrow down to non-cursor planes on the same CRTC as the cursor */
>   		if (new_underlying_state->crtc != crtc || underlying == crtc->cursor)
-- 
Hamza