Merge tag 'drm-misc-fixes-2017-12-06' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

Just the connector_iter corner-case regression fix.

* tag 'drm-misc-fixes-2017-12-06' of git://anongit.freedesktop.org/drm/drm-misc:
  drm: safely free connectors from connector_iter
This commit is contained in:
Dave Airlie 2017-12-07 08:29:26 +10:00
commit bd3a3a2e92
3 changed files with 36 additions and 2 deletions

View File

@ -152,6 +152,16 @@ static void drm_connector_free(struct kref *kref)
connector->funcs->destroy(connector);
}
static void drm_connector_free_work_fn(struct work_struct *work)
{
struct drm_connector *connector =
container_of(work, struct drm_connector, free_work);
struct drm_device *dev = connector->dev;
drm_mode_object_unregister(dev, &connector->base);
connector->funcs->destroy(connector);
}
/**
* drm_connector_init - Init a preallocated connector
* @dev: DRM device
@ -181,6 +191,8 @@ int drm_connector_init(struct drm_device *dev,
if (ret)
return ret;
INIT_WORK(&connector->free_work, drm_connector_free_work_fn);
connector->base.properties = &connector->properties;
connector->dev = dev;
connector->funcs = funcs;
@ -529,6 +541,18 @@ void drm_connector_list_iter_begin(struct drm_device *dev,
}
EXPORT_SYMBOL(drm_connector_list_iter_begin);
/*
* Extra-safe connector put function that works in any context. Should only be
* used from the connector_iter functions, where we never really expect to
* actually release the connector when dropping our final reference.
*/
static void
drm_connector_put_safe(struct drm_connector *conn)
{
if (refcount_dec_and_test(&conn->base.refcount.refcount))
schedule_work(&conn->free_work);
}
/**
* drm_connector_list_iter_next - return next connector
* @iter: connectr_list iterator
@ -561,7 +585,7 @@ drm_connector_list_iter_next(struct drm_connector_list_iter *iter)
spin_unlock_irqrestore(&config->connector_list_lock, flags);
if (old_conn)
drm_connector_put(old_conn);
drm_connector_put_safe(old_conn);
return iter->conn;
}
@ -580,7 +604,7 @@ void drm_connector_list_iter_end(struct drm_connector_list_iter *iter)
{
iter->dev = NULL;
if (iter->conn)
drm_connector_put(iter->conn);
drm_connector_put_safe(iter->conn);
lock_release(&connector_list_iter_dep_map, 0, _RET_IP_);
}
EXPORT_SYMBOL(drm_connector_list_iter_end);

View File

@ -431,6 +431,8 @@ void drm_mode_config_cleanup(struct drm_device *dev)
drm_connector_put(connector);
}
drm_connector_list_iter_end(&conn_iter);
/* connector_iter drops references in a work item. */
flush_scheduled_work();
if (WARN_ON(!list_empty(&dev->mode_config.connector_list))) {
drm_connector_list_iter_begin(dev, &conn_iter);
drm_for_each_connector_iter(connector, &conn_iter)

View File

@ -916,6 +916,14 @@ struct drm_connector {
uint8_t num_h_tile, num_v_tile;
uint8_t tile_h_loc, tile_v_loc;
uint16_t tile_h_size, tile_v_size;
/**
* @free_work:
*
* Work used only by &drm_connector_iter to be able to clean up a
* connector from any context.
*/
struct work_struct free_work;
};
#define obj_to_connector(x) container_of(x, struct drm_connector, base)