drm/dp/mst: Remove port after removing connector.
The port is removed synchronously, but the connector delayed.
This causes a use after free which can cause a kernel BUG with
slug_debug=FPZU. This is fixed by freeing the port after the
connector.
This fixes a regression introduced with
6b8eeca65b18ae77e175cc2b6571731f0ee413bf
"drm/dp/mst: close deadlock in connector destruction."
Cc: stable@vger.kernel.org
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 778bbb6..1325eec 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -873,9 +873,10 @@
from an EDID retrieval */
if (port->connector) {
mutex_lock(&mgr->destroy_connector_lock);
- list_add(&port->connector->destroy_list, &mgr->destroy_connector_list);
+ list_add(&port->next, &mgr->destroy_connector_list);
mutex_unlock(&mgr->destroy_connector_lock);
schedule_work(&mgr->destroy_connector_work);
+ return;
}
drm_dp_port_teardown_pdt(port, port->pdt);
@@ -2660,7 +2661,7 @@
static void drm_dp_destroy_connector_work(struct work_struct *work)
{
struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
- struct drm_connector *connector;
+ struct drm_dp_mst_port *port;
/*
* Not a regular list traverse as we have to drop the destroy
@@ -2669,15 +2670,21 @@
*/
for (;;) {
mutex_lock(&mgr->destroy_connector_lock);
- connector = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_connector, destroy_list);
- if (!connector) {
+ port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next);
+ if (!port) {
mutex_unlock(&mgr->destroy_connector_lock);
break;
}
- list_del(&connector->destroy_list);
+ list_del(&port->next);
mutex_unlock(&mgr->destroy_connector_lock);
- mgr->cbs->destroy_connector(mgr, connector);
+ mgr->cbs->destroy_connector(mgr, port->connector);
+
+ drm_dp_port_teardown_pdt(port, port->pdt);
+
+ if (!port->input && port->vcpi.vcpi > 0)
+ drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
+ kfree(port);
}
}
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 57ca8cc..3b4d8a4 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -743,8 +743,6 @@
uint8_t num_h_tile, num_v_tile;
uint8_t tile_h_loc, tile_v_loc;
uint16_t tile_h_size, tile_v_size;
-
- struct list_head destroy_list;
};
/**