Merge branch 'net-reduce-dynamic-lockdep-keys'

Cong Wang says:

====================
net: reduce dynamic lockdep keys

syzbot has been complaining about low MAX_LOCKDEP_KEYS for a
long time, it is mostly because we register 4 dynamic keys per
network device.

This patchset reduces the number of dynamic lockdep keys from
4 to 1 per netdev, by reverting to the previous static keys,
except for addr_list_lock which still has to be dynamic.
The second patch removes a bonding-specific key by the way.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -4491,7 +4491,6 @@ static void bond_uninit(struct net_device *bond_dev)
 
 	list_del(&bond->bond_list);
 
-	lockdep_unregister_key(&bond->stats_lock_key);
 	bond_debug_unregister(bond);
 }
 
@@ -4896,8 +4895,7 @@ static int bond_init(struct net_device *bond_dev)
 		return -ENOMEM;
 
 	spin_lock_init(&bond->stats_lock);
-	lockdep_register_key(&bond->stats_lock_key);
+	netdev_lockdep_set_classes(bond_dev);
-	lockdep_set_class(&bond->stats_lock, &bond->stats_lock_key);
 
 	list_add_tail(&bond->bond_list, &bn->dev_list);
 

drivers/net/ethernet/netronome/nfp/nfp_net_repr.c

@@ -299,6 +299,20 @@ static void nfp_repr_clean(struct nfp_repr *repr)
 	nfp_port_free(repr->port);
 }
 
+static struct lock_class_key nfp_repr_netdev_xmit_lock_key;
+
+static void nfp_repr_set_lockdep_class_one(struct net_device *dev,
+					   struct netdev_queue *txq,
+					   void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &nfp_repr_netdev_xmit_lock_key);
+}
+
+static void nfp_repr_set_lockdep_class(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, nfp_repr_set_lockdep_class_one, NULL);
+}
+
 int nfp_repr_init(struct nfp_app *app, struct net_device *netdev,
 		  u32 cmsg_port_id, struct nfp_port *port,
 		  struct net_device *pf_netdev)
@@ -308,6 +322,8 @@ int nfp_repr_init(struct nfp_app *app, struct net_device *netdev,
 	u32 repr_cap = nn->tlv_caps.repr_cap;
 	int err;
 
+	nfp_repr_set_lockdep_class(netdev);
+
 	repr->port = port;
 	repr->dst = metadata_dst_alloc(0, METADATA_HW_PORT_MUX, GFP_KERNEL);
 	if (!repr->dst)

drivers/net/hamradio/bpqether.c

@@ -107,6 +107,25 @@ struct bpqdev {
 
 static LIST_HEAD(bpq_devices);
 
+/*
+ * bpqether network devices are paired with ethernet devices below them, so
+ * form a special "super class" of normal ethernet devices; split their locks
+ * off into a separate class since they always nest.
+ */
+static struct lock_class_key bpq_netdev_xmit_lock_key;
+
+static void bpq_set_lockdep_class_one(struct net_device *dev,
+				      struct netdev_queue *txq,
+				      void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &bpq_netdev_xmit_lock_key);
+}
+
+static void bpq_set_lockdep_class(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, bpq_set_lockdep_class_one, NULL);
+}
+
 /* ------------------------------------------------------------------------ */
 
 
@@ -477,6 +496,7 @@ static int bpq_new_device(struct net_device *edev)
 	err = register_netdevice(ndev);
 	if (err)
 		goto error;
+	bpq_set_lockdep_class(ndev);
 
 	/* List protected by RTNL */
 	list_add_rcu(&bpq->bpq_list, &bpq_devices);

drivers/net/hyperv/netvsc_drv.c

@@ -2456,6 +2456,8 @@ static int netvsc_probe(struct hv_device *dev,
 		NETIF_F_HW_VLAN_CTAG_RX;
 	net->vlan_features = net->features;
 
+	netdev_lockdep_set_classes(net);
+
 	/* MTU range: 68 - 1500 or 65521 */
 	net->min_mtu = NETVSC_MTU_MIN;
 	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)

drivers/net/ipvlan/ipvlan_main.c

@@ -131,6 +131,8 @@ static int ipvlan_init(struct net_device *dev)
 	dev->gso_max_segs = phy_dev->gso_max_segs;
 	dev->hard_header_len = phy_dev->hard_header_len;
 
+	netdev_lockdep_set_classes(dev);
+
 	ipvlan->pcpu_stats = netdev_alloc_pcpu_stats(struct ipvl_pcpu_stats);
 	if (!ipvlan->pcpu_stats)
 		return -ENOMEM;

drivers/net/macsec.c

@@ -4047,6 +4047,8 @@ static int macsec_newlink(struct net *net, struct net_device *dev,
 	if (err < 0)
 		return err;
 
+	netdev_lockdep_set_classes(dev);
+
 	err = netdev_upper_dev_link(real_dev, dev, extack);
 	if (err < 0)
 		goto unregister;

drivers/net/macvlan.c

@@ -890,6 +890,8 @@ static int macvlan_init(struct net_device *dev)
 	dev->gso_max_segs	= lowerdev->gso_max_segs;
 	dev->hard_header_len	= lowerdev->hard_header_len;
 
+	netdev_lockdep_set_classes(dev);
+
 	vlan->pcpu_stats = netdev_alloc_pcpu_stats(struct vlan_pcpu_stats);
 	if (!vlan->pcpu_stats)
 		return -ENOMEM;

drivers/net/ppp/ppp_generic.c

@@ -1410,6 +1410,8 @@ static int ppp_dev_init(struct net_device *dev)
 {
 	struct ppp *ppp;
 
+	netdev_lockdep_set_classes(dev);
+
 	ppp = netdev_priv(dev);
 	/* Let the netdevice take a reference on the ppp file. This ensures
 	 * that ppp_destroy_interface() won't run before the device gets

drivers/net/team/team.c

@@ -1647,6 +1647,7 @@ static int team_init(struct net_device *dev)
 
 	lockdep_register_key(&team->team_lock_key);
 	__mutex_init(&team->lock, "team->team_lock_key", &team->team_lock_key);
+	netdev_lockdep_set_classes(dev);
 
 	return 0;
 

drivers/net/vrf.c

@@ -867,6 +867,7 @@ static int vrf_dev_init(struct net_device *dev)
 
 	/* similarly, oper state is irrelevant; set to up to avoid confusion */
 	dev->operstate = IF_OPER_UP;
+	netdev_lockdep_set_classes(dev);
 	return 0;
 
 out_rth:

drivers/net/wireless/intersil/hostap/hostap_hw.c

@@ -3041,6 +3041,27 @@ static void prism2_clear_set_tim_queue(local_info_t *local)
 	}
 }
 
+
+/*
+ * HostAP uses two layers of net devices, where the inner
+ * layer gets called all the time from the outer layer.
+ * This is a natural nesting, which needs a split lock type.
+ */
+static struct lock_class_key hostap_netdev_xmit_lock_key;
+
+static void prism2_set_lockdep_class_one(struct net_device *dev,
+					 struct netdev_queue *txq,
+					 void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock,
+			  &hostap_netdev_xmit_lock_key);
+}
+
+static void prism2_set_lockdep_class(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, prism2_set_lockdep_class_one, NULL);
+}
+
 static struct net_device *
 prism2_init_local_data(struct prism2_helper_functions *funcs, int card_idx,
 		       struct device *sdev)
@@ -3199,6 +3220,7 @@ while (0)
 	if (ret >= 0)
 		ret = register_netdevice(dev);
 
+	prism2_set_lockdep_class(dev);
 	rtnl_unlock();
 	if (ret < 0) {
 		printk(KERN_WARNING "%s: register netdevice failed!\n",

include/linux/netdevice.h

@@ -1805,13 +1805,11 @@ enum netdev_priv_flags {
  *	@phydev:	Physical device may attach itself
  *			for hardware timestamping
  *	@sfp_bus:	attached &struct sfp_bus structure.
- *	@qdisc_tx_busylock_key: lockdep class annotating Qdisc->busylock
+ *
- *				spinlock
- *	@qdisc_running_key:	lockdep class annotating Qdisc->running seqcount
- *	@qdisc_xmit_lock_key:	lockdep class annotating
- *				netdev_queue->_xmit_lock spinlock
  *	@addr_list_lock_key:	lockdep class annotating
  *				net_device->addr_list_lock spinlock
+ *	@qdisc_tx_busylock: lockdep class annotating Qdisc->busylock spinlock
+ *	@qdisc_running_key: lockdep class annotating Qdisc->running seqcount
  *
  *	@proto_down:	protocol port state information can be sent to the
  *			switch driver and used to set the phys state of the
@@ -2112,10 +2110,9 @@ struct net_device {
 #endif
 	struct phy_device	*phydev;
 	struct sfp_bus		*sfp_bus;
-	struct lock_class_key	qdisc_tx_busylock_key;
-	struct lock_class_key	qdisc_running_key;
-	struct lock_class_key	qdisc_xmit_lock_key;
 	struct lock_class_key	addr_list_lock_key;
+	struct lock_class_key	*qdisc_tx_busylock;
+	struct lock_class_key	*qdisc_running_key;
 	bool			proto_down;
 	unsigned		wol_enabled:1;
 
@@ -2200,6 +2197,20 @@ static inline void netdev_for_each_tx_queue(struct net_device *dev,
 		f(dev, &dev->_tx[i], arg);
 }
 
+#define netdev_lockdep_set_classes(dev)				\
+{								\
+	static struct lock_class_key qdisc_tx_busylock_key;	\
+	static struct lock_class_key qdisc_running_key;		\
+	static struct lock_class_key qdisc_xmit_lock_key;	\
+	unsigned int i;						\
+								\
+	(dev)->qdisc_tx_busylock = &qdisc_tx_busylock_key;	\
+	(dev)->qdisc_running_key = &qdisc_running_key;		\
+	for (i = 0; i < (dev)->num_tx_queues; i++)		\
+		lockdep_set_class(&(dev)->_tx[i]._xmit_lock,	\
+				  &qdisc_xmit_lock_key);	\
+}
+
 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb,
 		     struct net_device *sb_dev);
 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev,

include/net/bonding.h

@@ -237,7 +237,6 @@ struct bonding {
 	struct	 dentry *debug_dir;
 #endif /* CONFIG_DEBUG_FS */
 	struct rtnl_link_stats64 bond_stats;
-	struct lock_class_key stats_lock_key;
 };
 
 #define bond_slave_get_rcu(dev) \

net/8021q/vlan_dev.c

@@ -489,6 +489,25 @@ static void vlan_dev_set_rx_mode(struct net_device *vlan_dev)
 	dev_uc_sync(vlan_dev_priv(vlan_dev)->real_dev, vlan_dev);
 }
 
+/*
+ * vlan network devices have devices nesting below it, and are a special
+ * "super class" of normal network devices; split their locks off into a
+ * separate class since they always nest.
+ */
+static struct lock_class_key vlan_netdev_xmit_lock_key;
+
+static void vlan_dev_set_lockdep_one(struct net_device *dev,
+				     struct netdev_queue *txq,
+				     void *unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &vlan_netdev_xmit_lock_key);
+}
+
+static void vlan_dev_set_lockdep_class(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, vlan_dev_set_lockdep_one, NULL);
+}
+
 static const struct header_ops vlan_header_ops = {
 	.create	 = vlan_dev_hard_header,
 	.parse	 = eth_header_parse,
@@ -579,6 +598,8 @@ static int vlan_dev_init(struct net_device *dev)
 
 	SET_NETDEV_DEVTYPE(dev, &vlan_type);
 
+	vlan_dev_set_lockdep_class(dev);
+
 	vlan->vlan_pcpu_stats = netdev_alloc_pcpu_stats(struct vlan_pcpu_stats);
 	if (!vlan->vlan_pcpu_stats)
 		return -ENOMEM;

net/batman-adv/soft-interface.c

@@ -739,6 +739,34 @@ static int batadv_interface_kill_vid(struct net_device *dev, __be16 proto,
 	return 0;
 }
 
+/* batman-adv network devices have devices nesting below it and are a special
+ * "super class" of normal network devices; split their locks off into a
+ * separate class since they always nest.
+ */
+static struct lock_class_key batadv_netdev_xmit_lock_key;
+
+/**
+ * batadv_set_lockdep_class_one() - Set lockdep class for a single tx queue
+ * @dev: device which owns the tx queue
+ * @txq: tx queue to modify
+ * @_unused: always NULL
+ */
+static void batadv_set_lockdep_class_one(struct net_device *dev,
+					 struct netdev_queue *txq,
+					 void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &batadv_netdev_xmit_lock_key);
+}
+
+/**
+ * batadv_set_lockdep_class() - Set txq and addr_list lockdep class
+ * @dev: network device to modify
+ */
+static void batadv_set_lockdep_class(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, batadv_set_lockdep_class_one, NULL);
+}
+
 /**
  * batadv_softif_init_late() - late stage initialization of soft interface
  * @dev: registered network device to modify
@@ -752,6 +780,8 @@ static int batadv_softif_init_late(struct net_device *dev)
 	int ret;
 	size_t cnt_len = sizeof(u64) * BATADV_CNT_NUM;
 
+	batadv_set_lockdep_class(dev);
+
 	bat_priv = netdev_priv(dev);
 	bat_priv->soft_iface = dev;
 

net/bluetooth/6lowpan.c

@@ -571,7 +571,15 @@ static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
 	return err < 0 ? NET_XMIT_DROP : err;
 }
 
+static int bt_dev_init(struct net_device *dev)
+{
+	netdev_lockdep_set_classes(dev);
+
+	return 0;
+}
+
 static const struct net_device_ops netdev_ops = {
+	.ndo_init		= bt_dev_init,
 	.ndo_start_xmit		= bt_xmit,
 };
 

net/core/dev.c

@@ -398,6 +398,74 @@ static RAW_NOTIFIER_HEAD(netdev_chain);
 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
 EXPORT_PER_CPU_SYMBOL(softnet_data);
 
+#ifdef CONFIG_LOCKDEP
+/*
+ * register_netdevice() inits txq->_xmit_lock and sets lockdep class
+ * according to dev->type
+ */
+static const unsigned short netdev_lock_type[] = {
+	 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
+	 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
+	 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
+	 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
+	 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
+	 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
+	 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
+	 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
+	 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
+	 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
+	 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
+	 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
+	 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
+	 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
+	 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
+
+static const char *const netdev_lock_name[] = {
+	"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
+	"_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
+	"_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
+	"_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
+	"_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
+	"_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
+	"_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
+	"_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
+	"_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
+	"_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
+	"_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
+	"_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
+	"_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
+	"_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
+	"_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
+
+static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
+
+static inline unsigned short netdev_lock_pos(unsigned short dev_type)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
+		if (netdev_lock_type[i] == dev_type)
+			return i;
+	/* the last key is used by default */
+	return ARRAY_SIZE(netdev_lock_type) - 1;
+}
+
+static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
+						 unsigned short dev_type)
+{
+	int i;
+
+	i = netdev_lock_pos(dev_type);
+	lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
+				   netdev_lock_name[i]);
+}
+#else
+static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
+						 unsigned short dev_type)
+{
+}
+#endif
+
 /*******************************************************************************
  *
  *		Protocol management and registration routines
@@ -9208,7 +9276,7 @@ static void netdev_init_one_queue(struct net_device *dev,
 {
 	/* Initialize queue lock */
 	spin_lock_init(&queue->_xmit_lock);
-	lockdep_set_class(&queue->_xmit_lock, &dev->qdisc_xmit_lock_key);
+	netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
 	queue->xmit_lock_owner = -1;
 	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
 	queue->dev = dev;
@@ -9255,22 +9323,6 @@ void netif_tx_stop_all_queues(struct net_device *dev)
 }
 EXPORT_SYMBOL(netif_tx_stop_all_queues);
 
-static void netdev_register_lockdep_key(struct net_device *dev)
-{
-	lockdep_register_key(&dev->qdisc_tx_busylock_key);
-	lockdep_register_key(&dev->qdisc_running_key);
-	lockdep_register_key(&dev->qdisc_xmit_lock_key);
-	lockdep_register_key(&dev->addr_list_lock_key);
-}
-
-static void netdev_unregister_lockdep_key(struct net_device *dev)
-{
-	lockdep_unregister_key(&dev->qdisc_tx_busylock_key);
-	lockdep_unregister_key(&dev->qdisc_running_key);
-	lockdep_unregister_key(&dev->qdisc_xmit_lock_key);
-	lockdep_unregister_key(&dev->addr_list_lock_key);
-}
-
 void netdev_update_lockdep_key(struct net_device *dev)
 {
 	lockdep_unregister_key(&dev->addr_list_lock_key);
@@ -9837,7 +9889,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 
 	dev_net_set(dev, &init_net);
 
-	netdev_register_lockdep_key(dev);
+	lockdep_register_key(&dev->addr_list_lock_key);
 
 	dev->gso_max_size = GSO_MAX_SIZE;
 	dev->gso_max_segs = GSO_MAX_SEGS;
@@ -9926,7 +9978,7 @@ void free_netdev(struct net_device *dev)
 	free_percpu(dev->xdp_bulkq);
 	dev->xdp_bulkq = NULL;
 
-	netdev_unregister_lockdep_key(dev);
+	lockdep_unregister_key(&dev->addr_list_lock_key);
 
 	/*  Compatibility with error handling in drivers */
 	if (dev->reg_state == NETREG_UNINITIALIZED) {

net/dsa/slave.c

@@ -1671,6 +1671,15 @@ static int dsa_slave_phy_setup(struct net_device *slave_dev)
 	return ret;
 }
 
+static struct lock_class_key dsa_slave_netdev_xmit_lock_key;
+static void dsa_slave_set_lockdep_class_one(struct net_device *dev,
+					    struct netdev_queue *txq,
+					    void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock,
+			  &dsa_slave_netdev_xmit_lock_key);
+}
+
 int dsa_slave_suspend(struct net_device *slave_dev)
 {
 	struct dsa_port *dp = dsa_slave_to_port(slave_dev);
@@ -1754,6 +1763,9 @@ int dsa_slave_create(struct dsa_port *port)
 		slave_dev->max_mtu = ETH_MAX_MTU;
 	SET_NETDEV_DEVTYPE(slave_dev, &dsa_type);
 
+	netdev_for_each_tx_queue(slave_dev, dsa_slave_set_lockdep_class_one,
+				 NULL);
+
 	SET_NETDEV_DEV(slave_dev, port->ds->dev);
 	slave_dev->dev.of_node = port->dn;
 	slave_dev->vlan_features = master->vlan_features;

net/ieee802154/6lowpan/core.c

@@ -58,6 +58,13 @@ static const struct header_ops lowpan_header_ops = {
 	.create	= lowpan_header_create,
 };
 
+static int lowpan_dev_init(struct net_device *ldev)
+{
+	netdev_lockdep_set_classes(ldev);
+
+	return 0;
+}
+
 static int lowpan_open(struct net_device *dev)
 {
 	if (!open_count)
@@ -89,6 +96,7 @@ static int lowpan_get_iflink(const struct net_device *dev)
 }
 
 static const struct net_device_ops lowpan_netdev_ops = {
+	.ndo_init		= lowpan_dev_init,
 	.ndo_start_xmit		= lowpan_xmit,
 	.ndo_open		= lowpan_open,
 	.ndo_stop		= lowpan_stop,

net/l2tp/l2tp_eth.c

@@ -56,6 +56,7 @@ static int l2tp_eth_dev_init(struct net_device *dev)
 {
 	eth_hw_addr_random(dev);
 	eth_broadcast_addr(dev->broadcast);
+	netdev_lockdep_set_classes(dev);
 
 	return 0;
 }

net/netrom/af_netrom.c

@@ -63,6 +63,26 @@ static DEFINE_SPINLOCK(nr_list_lock);
 
 static const struct proto_ops nr_proto_ops;
 
+/*
+ * NETROM network devices are virtual network devices encapsulating NETROM
+ * frames into AX.25 which will be sent through an AX.25 device, so form a
+ * special "super class" of normal net devices; split their locks off into a
+ * separate class since they always nest.
+ */
+static struct lock_class_key nr_netdev_xmit_lock_key;
+
+static void nr_set_lockdep_one(struct net_device *dev,
+			       struct netdev_queue *txq,
+			       void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &nr_netdev_xmit_lock_key);
+}
+
+static void nr_set_lockdep_key(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, nr_set_lockdep_one, NULL);
+}
+
 /*
  *	Socket removal during an interrupt is now safe.
  */
@@ -1394,6 +1414,7 @@ static int __init nr_proto_init(void)
 			free_netdev(dev);
 			goto fail;
 		}
+		nr_set_lockdep_key(dev);
 		dev_nr[i] = dev;
 	}
 

net/rose/af_rose.c

@@ -64,6 +64,26 @@ static const struct proto_ops rose_proto_ops;
 
 ax25_address rose_callsign;
 
+/*
+ * ROSE network devices are virtual network devices encapsulating ROSE
+ * frames into AX.25 which will be sent through an AX.25 device, so form a
+ * special "super class" of normal net devices; split their locks off into a
+ * separate class since they always nest.
+ */
+static struct lock_class_key rose_netdev_xmit_lock_key;
+
+static void rose_set_lockdep_one(struct net_device *dev,
+				 struct netdev_queue *txq,
+				 void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &rose_netdev_xmit_lock_key);
+}
+
+static void rose_set_lockdep_key(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, rose_set_lockdep_one, NULL);
+}
+
 /*
  *	Convert a ROSE address into text.
  */
@@ -1511,6 +1531,7 @@ static int __init rose_proto_init(void)
 			free_netdev(dev);
 			goto fail;
 		}
+		rose_set_lockdep_key(dev);
 		dev_rose[i] = dev;
 	}
 

net/sched/sch_generic.c

@@ -794,6 +794,9 @@ struct Qdisc_ops pfifo_fast_ops __read_mostly = {
 };
 EXPORT_SYMBOL(pfifo_fast_ops);
 
+static struct lock_class_key qdisc_tx_busylock;
+static struct lock_class_key qdisc_running_key;
+
 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 			  const struct Qdisc_ops *ops,
 			  struct netlink_ext_ack *extack)
@@ -846,9 +849,17 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 	}
 
 	spin_lock_init(&sch->busylock);
+	lockdep_set_class(&sch->busylock,
+			  dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
+
 	/* seqlock has the same scope of busylock, for NOLOCK qdisc */
 	spin_lock_init(&sch->seqlock);
+	lockdep_set_class(&sch->busylock,
+			  dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
+
 	seqcount_init(&sch->running);
+	lockdep_set_class(&sch->running,
+			  dev->qdisc_running_key ?: &qdisc_running_key);
 
 	sch->ops = ops;
 	sch->flags = ops->static_flags;
@@ -859,12 +870,6 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 	dev_hold(dev);
 	refcount_set(&sch->refcnt, 1);
 
-	if (sch != &noop_qdisc) {
-		lockdep_set_class(&sch->busylock, &dev->qdisc_tx_busylock_key);
-		lockdep_set_class(&sch->seqlock, &dev->qdisc_tx_busylock_key);
-		lockdep_set_class(&sch->running, &dev->qdisc_running_key);
-	}
-
 	return sch;
 errout1:
 	kfree(p);