Willem de Bruijn [off-list ref] writes:

quoted

 static int cake_init(struct Qdisc *sch, struct nlattr *opt,
 		     struct netlink_ext_ack *extack)
 {
-	struct cake_sched_data *q = qdisc_priv(sch);
+	struct cake_sched_data *qd = qdisc_priv(sch);
+	struct cake_sched_config *q;
 	int i, j, err;
 
+	q = kvcalloc(1, sizeof(struct cake_sched_config), GFP_KERNEL);
+	if (!q)
+		return -ENOMEM;
+

Can this just be a regular kzalloc?

Yeah, I guess so. I'll change this if there's a need to respin for other
reasons, but probably not worth respinning for this on its own? Seeing
as it'll all end up in the same kmalloc call anyway :)

More importantly, where is q assigned to qd->config after init?

Just below:

quoted

 	sch->limit = 10240;
 	sch->flags |= TCQ_F_DEQUEUE_DROPS;
 

@@ -2742,33 +2755,36 @@ static int cake_init(struct Qdisc *sch, struct nlattr *opt,
 			       * for 5 to 10% of interval
 			       */
 	q->rate_flags |= CAKE_FLAG_SPLIT_GSO;
-	q->cur_tin = 0;
-	q->cur_flow  = 0;
+	qd->cur_tin = 0;
+	qd->cur_flow  = 0;
+	qd->config = q;

Here:   ^^^^^^^

-Toke