Re: [PATCH 1/2] net: sched: make default fifo qdiscs appear in the dump

[David Miller]

From: Jiri Kosina <jikos@xxxxxxxxxx>
Date: Sat, 25 Feb 2017 22:29:09 +0100 (CET)

> @@ -1066,6 +1066,7 @@ hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
>  				      &pfifo_qdisc_ops, classid);
>  	if (cl->qdisc == NULL)
>  		cl->qdisc = &noop_qdisc;
> +	qdisc_hash_add(cl->qdisc, true);
>  	INIT_LIST_HEAD(&cl->children);
>  	cl->vt_tree = RB_ROOT;
>  	cl->cf_tree = RB_ROOT;
> @@ -1425,6 +1426,7 @@ hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt)
>  					  sch->handle);
>  	if (q->root.qdisc == NULL)
>  		q->root.qdisc = &noop_qdisc;
> +	qdisc_hash_add(q->root.qdisc, true);
>  	INIT_LIST_HEAD(&q->root.children);
>  	q->root.vt_tree = RB_ROOT;
>  	q->root.cf_tree = RB_ROOT;

I'm not so sure it is legal is potentially pass &noop_qdisc into qdisc_hash_add().