[ANNOUNCE] v5.15.2-rt20

[Sebastian Andrzej Siewior]

Dear RT folks!

I'm pleased to announce the v5.15.2-rt20 patch set. 

Changes since v5.15.2-rt19:

  - A patch from upstream to avoid a "larg stack frame" warning.

Known issues
     - netconsole triggers WARN.

     - The "Memory controller" (CONFIG_MEMCG) has been disabled.

     - Valentin Schneider reported a few splats on ARM64, see
          https://lkml.kernel.org/r/20210810134127.1394269-1-valentin.schneider@xxxxxxx

The delta patch against v5.15.2-rt19 is appended below and can be found here:
 
     https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.15/incr/patch-5.15.2-rt19-rt20.patch.xz

You can get this release via the git tree at:

    git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git v5.15.2-rt20

The RT patch against v5.15.2 can be found here:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.15/older/patch-5.15.2-rt20.patch.xz

The split quilt queue is available at:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.15/older/patches-5.15.2-rt20.tar.xz

Sebastian

diff --git a/localversion-rt b/localversion-rt
index 483ad771f201a..e095ab8197147 100644
--- a/localversion-rt
+++ b/localversion-rt
@@ -1 +1 @@
--rt19
+-rt20
diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c
index 72de08ef8335e..1073c76d05c45 100644
--- a/net/sched/sch_gred.c
+++ b/net/sched/sch_gred.c
@@ -56,6 +56,7 @@ struct gred_sched {
 	u32 		DPs;
 	u32 		def;
 	struct red_vars wred_set;
+	struct tc_gred_qopt_offload *opt;
 };
 
 static inline int gred_wred_mode(struct gred_sched *table)
@@ -311,42 +312,43 @@ static void gred_offload(struct Qdisc *sch, enum tc_gred_command command)
 {
 	struct gred_sched *table = qdisc_priv(sch);
 	struct net_device *dev = qdisc_dev(sch);
-	struct tc_gred_qopt_offload opt = {
-		.command	= command,
-		.handle		= sch->handle,
-		.parent		= sch->parent,
-	};
+	struct tc_gred_qopt_offload *opt = table->opt;
 
 	if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
 		return;
 
+	memset(opt, 0, sizeof(*opt));
+	opt->command = command;
+	opt->handle = sch->handle;
+	opt->parent = sch->parent;
+
 	if (command == TC_GRED_REPLACE) {
 		unsigned int i;
 
-		opt.set.grio_on = gred_rio_mode(table);
-		opt.set.wred_on = gred_wred_mode(table);
-		opt.set.dp_cnt = table->DPs;
-		opt.set.dp_def = table->def;
+		opt->set.grio_on = gred_rio_mode(table);
+		opt->set.wred_on = gred_wred_mode(table);
+		opt->set.dp_cnt = table->DPs;
+		opt->set.dp_def = table->def;
 
 		for (i = 0; i < table->DPs; i++) {
 			struct gred_sched_data *q = table->tab[i];
 
 			if (!q)
 				continue;
-			opt.set.tab[i].present = true;
-			opt.set.tab[i].limit = q->limit;
-			opt.set.tab[i].prio = q->prio;
-			opt.set.tab[i].min = q->parms.qth_min >> q->parms.Wlog;
-			opt.set.tab[i].max = q->parms.qth_max >> q->parms.Wlog;
-			opt.set.tab[i].is_ecn = gred_use_ecn(q);
-			opt.set.tab[i].is_harddrop = gred_use_harddrop(q);
-			opt.set.tab[i].probability = q->parms.max_P;
-			opt.set.tab[i].backlog = &q->backlog;
+			opt->set.tab[i].present = true;
+			opt->set.tab[i].limit = q->limit;
+			opt->set.tab[i].prio = q->prio;
+			opt->set.tab[i].min = q->parms.qth_min >> q->parms.Wlog;
+			opt->set.tab[i].max = q->parms.qth_max >> q->parms.Wlog;
+			opt->set.tab[i].is_ecn = gred_use_ecn(q);
+			opt->set.tab[i].is_harddrop = gred_use_harddrop(q);
+			opt->set.tab[i].probability = q->parms.max_P;
+			opt->set.tab[i].backlog = &q->backlog;
 		}
-		opt.set.qstats = &sch->qstats;
+		opt->set.qstats = &sch->qstats;
 	}
 
-	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_GRED, &opt);
+	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_GRED, opt);
 }
 
 static int gred_offload_dump_stats(struct Qdisc *sch)
@@ -731,6 +733,7 @@ static int gred_change(struct Qdisc *sch, struct nlattr *opt,
 static int gred_init(struct Qdisc *sch, struct nlattr *opt,
 		     struct netlink_ext_ack *extack)
 {
+	struct gred_sched *table = qdisc_priv(sch);
 	struct nlattr *tb[TCA_GRED_MAX + 1];
 	int err;
 
@@ -754,6 +757,12 @@ static int gred_init(struct Qdisc *sch, struct nlattr *opt,
 		sch->limit = qdisc_dev(sch)->tx_queue_len
 		             * psched_mtu(qdisc_dev(sch));
 
+	if (qdisc_dev(sch)->netdev_ops->ndo_setup_tc) {
+		table->opt = kzalloc(sizeof(*table->opt), GFP_KERNEL);
+		if (!table->opt)
+			return -ENOMEM;
+	}
+
 	return gred_change_table_def(sch, tb[TCA_GRED_DPS], extack);
 }
 
@@ -910,6 +919,7 @@ static void gred_destroy(struct Qdisc *sch)
 			gred_destroy_vq(table->tab[i]);
 	}
 	gred_offload(sch, TC_GRED_DESTROY);
+	kfree(table->opt);
 }
 
 static struct Qdisc_ops gred_qdisc_ops __read_mostly = {