weston: Add fix for using layer_entry_remove directly

Patch was proposed initially with a different fix upstream but
was changed a bit later.

Bug-AGL: SPEC-5105
Change-Id: I3fb6cc3d4a7b2a63b4296a2d36a998a55ccb8bc5
Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/29817
Tested-by: Scott Murray <scott.murray@konsulko.com>
Reviewed-by: Scott Murray <scott.murray@konsulko.com>

2 files changed, 61 insertions, 0 deletions

diff --git a/meta-agl-core/recipes-graphics/wayland/weston/0001-libweston-Add-paint-node-destruction-into-weston_lay.patch b/meta-agl-core/recipes-graphics/wayland/weston/0001-libweston-Add-paint-node-destruction-into-weston_lay.patch
new file mode 100644
index 000000000..19eadcf7f
--- /dev/null
+++ b/meta-agl-core/recipes-graphics/wayland/weston/0001-libweston-Add-paint-node-destruction-into-weston_lay.patch
@@ -0,0 +1,60 @@
+From cfde02d47a503cbfd0629bbfe0cb776686af8a91 Mon Sep 17 00:00:00 2001
+From: Marius Vlad <marius.vlad@collabora.com>
+Date: Tue, 9 Apr 2024 18:34:22 +0300
+Subject: [PATCH] libweston: Add paint node destruction into
+ weston_layer_entry_remove()
+
+This prevents a potential crash where users of
+weston_layer_entry_insert/layer_entry_remove() would see when moving
+views into a NULL layer (effectively unmapping the surface/view).
+
+Users that have migrated to the weston_view_move_to_layer() are immune
+to this issue because that takes care paint node destruction.
+
+Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
+---
+ libweston/compositor.c | 17 ++++++++++-------
+ 1 file changed, 10 insertions(+), 7 deletions(-)
+
+diff --git a/libweston/compositor.c b/libweston/compositor.c
+index bb29b83b5..ea257bb90 100644
+--- a/libweston/compositor.c
++++ b/libweston/compositor.c
+@@ -3980,17 +3980,10 @@ weston_view_move_to_layer(struct weston_view *view,
+ 			  struct weston_layer_entry *layer)
+ {
+ 	bool was_mapped = view->is_mapped;
+-	struct weston_paint_node *pnode, *pntmp;
+ 
+ 	if (layer == &view->layer_link)
+ 		return;
+ 
+-	/* Remove all paint nodes because we have no idea what a layer change
+-	 * does to view visibility on any output.
+-	 */
+-	wl_list_for_each_safe(pnode, pntmp, &view->paint_node_list, view_link)
+-		weston_paint_node_destroy(pnode);
+-
+ 	view->surface->compositor->view_list_needs_rebuild = true;
+ 
+ 	/* Damage the view's old region, and remove it from the layer. */
+@@ -4020,6 +4013,16 @@ weston_view_move_to_layer(struct weston_view *view,
+ WL_EXPORT void
+ weston_layer_entry_remove(struct weston_layer_entry *entry)
+ {
++	struct weston_paint_node *pnode, *pntmp;
++	struct weston_view *view;
++
++	/* Remove all paint nodes because we have no idea what a layer change
++	 * does to view visibility on any output.
++	 */
++	view = container_of(entry, struct weston_view, layer_link);
++	wl_list_for_each_safe(pnode, pntmp, &view->paint_node_list, view_link)
++		weston_paint_node_destroy(pnode);
++
+ 	wl_list_remove(&entry->link);
+ 	wl_list_init(&entry->link);
+ 	entry->layer = NULL;
+-- 
+2.43.0
+
diff --git a/meta-agl-core/recipes-graphics/wayland/weston_13.0_aglcore.inc b/meta-agl-core/recipes-graphics/wayland/weston_13.0_aglcore.inc
index 14387898e..843a068b4 100644
--- a/meta-agl-core/recipes-graphics/wayland/weston_13.0_aglcore.inc
+++ b/meta-agl-core/recipes-graphics/wayland/weston_13.0_aglcore.inc
@@ -4,6 +4,7 @@ PACKAGECONFIG:append = "${@bb.utils.contains('DISTRO_FEATURES', 'weston-remoting
 
 SRC_URI:append = " \
 		  file://0001-clients-Handle-missing-pointer_surface-is-there-s-no.patch \
+		  file://0001-libweston-Add-paint-node-destruction-into-weston_lay.patch \
 "