On Wed, Aug 21, 2019 at 08:41:32AM -0700, Bart Van Assche wrote: > On 8/20/19 8:00 PM, Ming Lei wrote: > > On Tue, Aug 20, 2019 at 02:21:10PM -0700, Bart Van Assche wrote: > > > - /* > > > - * Remove the sysfs attributes before unregistering the queue data > > > - * structures that can be modified through sysfs. > > > - */ > > > if (queue_is_mq(q)) > > > - blk_mq_unregister_dev(disk_to_dev(disk), q); > > > - mutex_unlock(&q->sysfs_lock); > > > - > > > + kobject_uevent(q->mq_kobj, KOBJ_REMOVE); > > > > Could you explain why you move the above line here? > > I'm not sure whether kobject_del() deletes any objects attached to the > deleted kobj. This change ensures that kobject_uevent() is called before the > parent object of q->mq_kobj is deleted. >From comment of kernfs_remove(), all subdirectories and files will be removed. kobject_del sysfs_remove_dir kernfs_remove /** * kernfs_remove - remove a kernfs_node recursively * @kn: the kernfs_node to remove * * Remove @kn along with all its subdirectories and files. */ void kernfs_remove(struct kernfs_node *kn) Thanks, Ming
