[PATCH v2 1/6] compositor: set surface->plane from destroyed plane to NULL

[Xiong Zhang]

In drm backend, the cursor_surface->plane point to
drm_output->cursor_plane.when this output is removed,
drm_output->cursor_plane is destroyed, butcursor_surface->plane
still point to destroyed plane. So once mouse move to this
cursor_surface and system will repaint this cursor_surface,
segment fault will generate in weston_surface_damage_below() function.

V2:
-set surface->plane to NULL whose plane point to unplugged output,
 then change weston_surface_damage_below() to do nothing if
 surface->plane is NULL (Kristian)
-set surface->plane to NULL in weston_surface_unmap(),
 so that all surfaces that have a non-NULL plane pointer wil be
 on compositor->surface_list (Kristian).

bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=69777

Signed-off-by: Xiong Zhang <xiong.y.zhang at intel.com>
---
 src/compositor-drm.c |  6 +++---
 src/compositor.c     | 22 +++++++++++++++++-----
 src/compositor.h     |  5 ++++-
 3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/src/compositor-drm.c b/src/compositor-drm.c
index ffdec89..b5c3051 100644
--- a/src/compositor-drm.c
+++ b/src/compositor-drm.c
@@ -1974,8 +1974,8 @@ create_output_for_connector(struct drm_compositor *ec,
 	output->base.gamma_size = output->original_crtc->gamma_size;
 	output->base.set_gamma = drm_output_set_gamma;
 
-	weston_plane_init(&output->cursor_plane, 0, 0);
-	weston_plane_init(&output->fb_plane, 0, 0);
+	weston_plane_init(&output->cursor_plane, &ec->base, 0, 0);
+	weston_plane_init(&output->fb_plane, &ec->base, 0, 0);
 
 	weston_compositor_stack_plane(&ec->base, &output->cursor_plane, NULL);
 	weston_compositor_stack_plane(&ec->base, &output->fb_plane,
@@ -2050,7 +2050,7 @@ create_sprites(struct drm_compositor *ec)
 		memcpy(sprite->formats, plane->formats,
 		       plane->count_formats * sizeof(plane->formats[0]));
 		drmModeFreePlane(plane);
-		weston_plane_init(&sprite->plane, 0, 0);
+		weston_plane_init(&sprite->plane, &ec->base, 0, 0);
 		weston_compositor_stack_plane(&ec->base, &sprite->plane,
 					      &ec->base.primary_plane);
 
diff --git a/src/compositor.c b/src/compositor.c
index 376ddfd..9eb3d5d 100644
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -377,7 +377,7 @@ weston_surface_create(struct weston_compositor *compositor)
 	surface->pending.buffer_transform = surface->buffer_transform;
 	surface->pending.buffer_scale = surface->buffer_scale;
 	surface->output = NULL;
-	surface->plane = &compositor->primary_plane;
+	surface->plane = NULL;
 	surface->pending.newly_attached = 0;
 
 	pixman_region32_init(&surface->damage);
@@ -578,8 +578,9 @@ weston_surface_damage_below(struct weston_surface *surface)
 	pixman_region32_init(&damage);
 	pixman_region32_subtract(&damage, &surface->transform.boundingbox,
 				 &surface->clip);
-	pixman_region32_union(&surface->plane->damage,
-			      &surface->plane->damage, &damage);
+	if (surface->plane)
+		pixman_region32_union(&surface->plane->damage,
+				&surface->plane->damage, &damage);
 	pixman_region32_fini(&damage);
 }
 
@@ -1056,6 +1057,7 @@ weston_surface_unmap(struct weston_surface *surface)
 
 	weston_surface_damage_below(surface);
 	surface->output = NULL;
+	surface->plane = NULL;
 	wl_list_remove(&surface->layer_link);
 	wl_list_remove(&surface->link);
 	wl_list_init(&surface->link);
@@ -2604,12 +2606,15 @@ idle_handler(void *data)
 }
 
 WL_EXPORT void
-weston_plane_init(struct weston_plane *plane, int32_t x, int32_t y)
+weston_plane_init(struct weston_plane *plane,
+			struct weston_compositor *ec,
+			int32_t x, int32_t y)
 {
 	pixman_region32_init(&plane->damage);
 	pixman_region32_init(&plane->clip);
 	plane->x = x;
 	plane->y = y;
+	plane->compositor = ec;
 
 	/* Init the link so that the call to wl_list_remove() when releasing
 	 * the plane without ever stacking doesn't lead to a crash */
@@ -2619,9 +2624,16 @@ weston_plane_init(struct weston_plane *plane, int32_t x, int32_t y)
 WL_EXPORT void
 weston_plane_release(struct weston_plane *plane)
 {
+	struct weston_surface *surface;
+
 	pixman_region32_fini(&plane->damage);
 	pixman_region32_fini(&plane->clip);
 
+	wl_list_for_each(surface, &plane->compositor->surface_list, link) {
+		if (surface->plane == plane)
+			surface->plane = NULL;
+	}
+
 	wl_list_remove(&plane->link);
 }
 
@@ -3015,7 +3027,7 @@ weston_compositor_init(struct weston_compositor *ec,
 	wl_list_init(&ec->axis_binding_list);
 	wl_list_init(&ec->debug_binding_list);
 
-	weston_plane_init(&ec->primary_plane, 0, 0);
+	weston_plane_init(&ec->primary_plane, ec, 0, 0);
 	weston_compositor_stack_plane(ec, &ec->primary_plane, NULL);
 
 	s = weston_config_get_section(ec->config, "keyboard", NULL, NULL);
diff --git a/src/compositor.h b/src/compositor.h
index a19d966..ae7008d 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -505,6 +505,7 @@ struct weston_layer {
 };
 
 struct weston_plane {
+	struct weston_compositor *compositor;
 	pixman_region32_t damage;
 	pixman_region32_t clip;
 	int32_t x, y;
@@ -927,7 +928,9 @@ void
 weston_layer_init(struct weston_layer *layer, struct wl_list *below);
 
 void
-weston_plane_init(struct weston_plane *plane, int32_t x, int32_t y);
+weston_plane_init(struct weston_plane *plane,
+			struct weston_compositor *ec,
+			int32_t x, int32_t y);
 void
 weston_plane_release(struct weston_plane *plane);
 
-- 
1.8.3.2