[PATCH weston 2/2] compositor-drm: the cursor plane only supports ARGB

[Bryce Harrington]

On Fri, Feb 05, 2016 at 02:30:22PM +0200, Pekka Paalanen wrote:
> On Thu,  3 Dec 2015 14:07:12 -0600
> Derek Foreman <derekf at osg.samsung.com> wrote:
> 
> > Keep XRGB apps out of the cursor plane, only ARGB is supported.
> > 
> > This prevents programs like weston-simple-shm from landing in the cursor
> > plane and being misrendered.
> > 
> > Signed-off-by: Derek Foreman <derekf at osg.samsung.com>
> > ---
> >  src/compositor-drm.c | 12 +++++++++---
> >  1 file changed, 9 insertions(+), 3 deletions(-)
> > 
> > diff --git a/src/compositor-drm.c b/src/compositor-drm.c
> > index a6db933..84105e1 100644
> > --- a/src/compositor-drm.c
> > +++ b/src/compositor-drm.c
> > @@ -1094,6 +1094,7 @@ drm_output_prepare_cursor_view(struct drm_output *output,
> >  	struct drm_backend *b =
> >  		(struct drm_backend *)output->base.compositor->backend;
> >  	struct weston_buffer_viewport *viewport = &ev->surface->buffer_viewport;
> > +	struct wl_shm_buffer *shmbuf;
> >  
> >  	if (ev->transform.enabled &&
> >  	    (ev->transform.matrix.type > WESTON_MATRIX_TRANSFORM_TRANSLATE))
> > @@ -1112,9 +1113,14 @@ drm_output_prepare_cursor_view(struct drm_output *output,
> >  		return NULL;
> >  	if (ev->geometry.scissor_enabled)
> >  		return NULL;
> > -	if (ev->surface->buffer_ref.buffer == NULL ||
> > -	    !wl_shm_buffer_get(ev->surface->buffer_ref.buffer->resource) ||
> > -	    ev->surface->width > b->cursor_width ||
> > +	if (ev->surface->buffer_ref.buffer == NULL)
> > +		return NULL;
> > +	shmbuf = wl_shm_buffer_get(ev->surface->buffer_ref.buffer->resource);
> > +	if (!shmbuf)
> > +		return NULL;
> > +	if (wl_shm_buffer_get_format(shmbuf) != WL_SHM_FORMAT_ARGB8888)
> > +		return NULL;
> > +	if (ev->surface->width > b->cursor_width ||
> >  	    ev->surface->height > b->cursor_height)
> >  		return NULL;
> >  
> 
> Reviewed-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
> 
> Also tested on intel SNB.
> 
> This will also prevent RGB565 surfaces going to the cursor plane, and
> cursor_bo_update() would just screw that up totally because it has a
> hardcoded "ev->surface->width * 4" in memcpy().
> 
> Not to mention that using surface dimensions for buffer access is...
> not good. drm_output_prepare_cursor_view() is accounting for
> buffer/output_scale and scissor, but it's missing viewport. It's also
> not checking buffer_transform. So if someone happened to use
> wl_viewport or buffer_transform on a small shm surface, we'd get funny
> stuff. But that's another matter, just noticed it while reviewing.

Thanks, pushed for rc1:
To ssh://git.freedesktop.org/git/wayland/weston
   b042756..6c19b69  master -> master