[PATCH] drm/amd/display: check fb of primary plane

[Harry Wentland]

On 2021-03-16 5:50 p.m., Sefa Eyeoglu wrote:
> Sometimes the primary plane might not be initialized (yet), which
> causes dm_check_crtc_cursor to divide by zero.
> Apparently a weird state before a S3-suspend causes the aforementioned
> divide-by-zero error when resuming from S3.  This was explained in
> bug 212293 on Bugzilla.
> 
> To avoid this divide-by-zero error we check if the primary plane's fb
> isn't NULL.  If it's NULL the src_w and src_h attributes will be 0,
> which would cause a divide-by-zero.
> 
> This fixes Bugzilla report 212293
> https://bugzilla.kernel.org/show_bug.cgi?id=212293>> 
> Fixes: 12f4849a1cfd69f3 ("drm/amd/display: check cursor scaling")
> Signed-off-by: Sefa Eyeoglu <contact at scrumplex.net>

Thanks for your patch.

It is
Reviewed-by: Harry Wentland <harry.wentland at amd.com>

Harry

> ---
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> 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 573cf17262da4e11..fbb1ac223ccbb62a 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -9267,7 +9267,8 @@ static int dm_check_crtc_cursor(struct drm_atomic_state *state,
>   
>   	new_cursor_state = drm_atomic_get_new_plane_state(state, crtc->cursor);
>   	new_primary_state = drm_atomic_get_new_plane_state(state, crtc->primary);
> -	if (!new_cursor_state || !new_primary_state || !new_cursor_state->fb) {
> +	if (!new_cursor_state || !new_primary_state ||
> +		!new_cursor_state->fb || !new_primary_state->fb) {
>   		return 0;
>   	}
>   
>