On Wed, Nov 02, 2016 at 10:27:44AM -0400, Rob Clark wrote:
> drm-hwc + android tries to create an fb for the wallpaper layer, which
> is larger than the screen resolution, and potentially larger than
> mode_config->max_{width,height}. But the plane src_w/src_h is within
> the max limits, so it is something the hardware can otherwise do.
>
> For atomic drivers, defer the check to drm_atomic_plane_check().
>
> Signed-off-by: Rob Clark <robdclark at gmail.com>
> ---
> drivers/gpu/drm/drm_atomic.c | 17 +++++++++++++++++
> drivers/gpu/drm/drm_crtc.c | 26 +++++++++++++++++---------
> 2 files changed, 34 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index 34edd4f..fb0f07ce 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -846,7 +846,9 @@ plane_switching_crtc(struct drm_atomic_state *state,
> static int drm_atomic_plane_check(struct drm_plane *plane,
> struct drm_plane_state *state)
> {
> + struct drm_mode_config *config = &plane->dev->mode_config;
> unsigned int fb_width, fb_height;
> + unsigned int min_width, max_width, min_height, max_height;
> int ret;
>
> /* either *both* CRTC and FB must be set, or neither */
> @@ -909,6 +911,21 @@ static int drm_atomic_plane_check(struct drm_plane
> *plane,
> return -ENOSPC;
> }
>
> + min_width = config->min_width << 16;
> + max_width = config->max_width << 16;
> + min_height = config->min_height << 16;
> + max_height = config->max_height << 16;
> +
> + /* Make sure source dimensions are within bounds. */
> + if (min_width > state->src_w || state->src_w > max_width ||
> + min_height > state->src_h || state->src_h > max_height) {
> + DRM_DEBUG_ATOMIC("Invalid source size "
> + "%u.%06ux%u.%06u\n",
> + state->src_w >> 16, ((state->src_w & 0xffff) *
> 15625) >> 10,
> + state->src_h >> 16, ((state->src_h & 0xffff) *
> 15625) >> 10);
> + return -ERANGE;
> + }
> +
> if (plane_switching_crtc(state->state, plane, state)) {
> DRM_DEBUG_ATOMIC("[PLANE:%d:%s] switching CRTC directly\n",
> plane->base.id, plane->name);
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index b4b973f..7294bde 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -3369,15 +3369,23 @@ internal_framebuffer_create(struct drm_device *dev,
> return ERR_PTR(-EINVAL);
> }
>
> - if ((config->min_width > r->width) || (r->width > config->max_width)) {
> - DRM_DEBUG_KMS("bad framebuffer width %d, should be >= %d && <=
> %d\n",
> - r->width, config->min_width, config->max_width);
> - return ERR_PTR(-EINVAL);
> - }
> - if ((config->min_height > r->height) || (r->height >
> config->max_height)) {
> - DRM_DEBUG_KMS("bad framebuffer height %d, should be >= %d && <=
> %d\n",
> - r->height, config->min_height, config->max_height);
> - return ERR_PTR(-EINVAL);
> + /* for atomic drivers, we check the src dimensions in
> + * drm_atomic_plane_check().. allow creation of a fb
> + * that is larger than what can be scanned out, as
> + * long as userspace doesn't try to scanout a portion
> + * of the fb that is too large.
> + */
> + if (!file_priv->atomic) {
> + if ((config->min_width > r->width) || (r->width >
> config->max_width)) {
> + DRM_DEBUG_KMS("bad framebuffer width %d, should be >=
> %d && <= %d\n",
> + r->width, config->min_width,
> config->max_width);
> + return ERR_PTR(-EINVAL);
> + }
> + if ((config->min_height > r->height) || (r->height >
> config->max_height)) {
> + DRM_DEBUG_KMS("bad framebuffer height %d, should be >=
> %d && <= %d\n",
> + r->height, config->min_height,
> config->max_height);
> + return ERR_PTR(-EINVAL);
> + }
So why not just bump max_foo in your driver?
Removing the restriction from the core seems likely to break some
drivers as they would now have to check the fb dimensions themselves.
> }
>
> if (r->flags & DRM_MODE_FB_MODIFIERS &&
> --
> 2.7.4
--
Ville Syrjälä
Intel OTC
