[PATCH 1/2] drm/atomic: Update old_fb after setting a property.

[Rob Clark]

On Wed, Jun 24, 2015 at 2:59 AM, Maarten Lankhorst
<maarten.lankhorst at linux.intel.com> wrote:
> This change updates the old_fb pointer only after acquiring the plane lock,
> if there are no properties the fb cannot have been changed either, so
> this works out correctly.
>
> Found in a discussion with Rob Clark.
>
> Cc: Rob Clark <robdclark at gmail.com>
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>

Reviewed-by: Rob Clark <robdclark at gmail.com>

> ---
>  drivers/gpu/drm/drm_atomic.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index f6f2fb58eb37..bd7f723c708e 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -1472,12 +1472,6 @@ retry:
>                         goto fail;
>                 }
>
> -               if (obj->type == DRM_MODE_OBJECT_PLANE) {
> -                       plane = obj_to_plane(obj);
> -                       plane_mask |= (1 << drm_plane_index(plane));
> -                       plane->old_fb = plane->fb;
> -               }
> -
>                 if (get_user(count_props, count_props_ptr + copied_objs)) {
>                         ret = -EFAULT;
>                         goto fail;
> @@ -1514,6 +1508,12 @@ retry:
>
>                         copied_props++;
>                 }
> +
> +               if (obj->type == DRM_MODE_OBJECT_PLANE && count_props) {
> +                       plane = obj_to_plane(obj);
> +                       plane_mask |= (1 << drm_plane_index(plane));
> +                       plane->old_fb = plane->fb;
> +               }
>         }
>
>         if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
> --
> 2.1.0
>