drm/drv: Hold ref on parent device during drm_device lifetime (56be6503) · Commits · 戴 / test

This makes it safe to access drm_device->dev after the parent device has been removed/unplugged. Signed-off-by:

drivers/gpu/drm/drm_drv.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -521,7 +521,7 @@ int drm_dev_init(struct drm_device *dev,
		BUG_ON(!parent);

		kref_init(&dev->ref);
		dev->dev = parent;
		dev->dev = get_device(parent);
		dev->driver = driver;

		/* no per-device feature limits by default */
		@@ -591,6 +591,7 @@ err_minors:
		drm_minor_free(dev, DRM_MINOR_RENDER);
		drm_fs_inode_free(dev->anon_inode);
		err_free:
		put_device(dev->dev);
		mutex_destroy(&dev->master_mutex);
		mutex_destroy(&dev->ctxlist_mutex);
		mutex_destroy(&dev->clientlist_mutex);
		@@ -626,6 +627,8 @@ void drm_dev_fini(struct drm_device *dev)
		drm_minor_free(dev, DRM_MINOR_PRIMARY);
		drm_minor_free(dev, DRM_MINOR_RENDER);

		put_device(dev->dev);

		mutex_destroy(&dev->master_mutex);
		mutex_destroy(&dev->ctxlist_mutex);
		mutex_destroy(&dev->clientlist_mutex);