Merge branch 'geneve-make-geneve_fill_info-rtnl-less'

Eric Dumazet says: ==================== geneve: make geneve_fill_info() RTNL-less This series makes geneve_fill_info() independent of the RTNL lock by converting the device configuration to an RCU-protected pointer. Historically, geneve_changelink() updated the device configuration by copying the new configuration over the old one using memcpy() under RTNL. To prevent the transmit/receive data paths from reading torn values during the copy, geneve_quiesce() was used to pause the data path and wait for a synchronize_net(), causing packet loss and latency. By converting the configuration to an RCU-protected pointer, we can perform atomic updates via RCU swap. This allows data path readers to safely access the configuration locklessly under RCU read lock, and removes the need to stop the data path during changelink. With the RCU infrastructure in place, geneve_fill_info() is then updated to read the configuration under RCU read lock, removing its dependency on RTNL. v1: https://lore.kernel.org/netdev/20260701120454.3533252-1-edumazet@google.com/T/#m887804321856d9b5c7142107e81b52553e60e6ab ==================== Link: https://patch.msgid.link/20260707145331.3717941-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-31 04:46:30 -04:00 · 2026-07-21 09:37:42 +02:00
parent 1e4aed51b7 5415c41a83
commit bbc93a389e
1 changed files with 209 additions and 161 deletions
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -82,6 +82,7 @@ struct geneve_config {
 	u16			port_min;
 	u16			port_max;

+	struct rcu_head		rcu;
 	/* Must be last --ends in a flexible-array member. */
 	struct ip_tunnel_info	info;
 };
@@ -100,7 +101,7 @@ struct geneve_dev {
 #endif
 	struct list_head   next;	/* geneve's per namespace list */
 	struct gro_cells   gro_cells;
-	struct geneve_config cfg;
+	struct geneve_config __rcu *cfg;
 };

 struct geneve_sock {
@@ -182,8 +183,10 @@ static struct geneve_dev *geneve_lookup(struct geneve_sock *gs,
 	hash = geneve_net_vni_hash(vni);
 	vni_list_head = &gs->vni_list[hash];
 	hlist_for_each_entry_rcu(node, vni_list_head, hlist) {
-		if (eq_tun_id_and_vni((u8 *)&node->geneve->cfg.info.key.tun_id, vni) &&
-		    addr == node->geneve->cfg.info.key.u.ipv4.dst)
+		const struct geneve_config *cfg = rcu_dereference(node->geneve->cfg);
+
+		if (eq_tun_id_and_vni((u8 *)&cfg->info.key.tun_id, vni) &&
+		    addr == cfg->info.key.u.ipv4.dst)
 			return node->geneve;
 	}
 	return NULL;
@@ -201,8 +204,10 @@ static struct geneve_dev *geneve6_lookup(struct geneve_sock *gs,
 	hash = geneve_net_vni_hash(vni);
 	vni_list_head = &gs->vni_list[hash];
 	hlist_for_each_entry_rcu(node, vni_list_head, hlist) {
-		if (eq_tun_id_and_vni((u8 *)&node->geneve->cfg.info.key.tun_id, vni) &&
-		    ipv6_addr_equal(&addr6, &node->geneve->cfg.info.key.u.ipv6.dst))
+		const struct geneve_config *cfg = rcu_dereference(node->geneve->cfg);
+
+		if (eq_tun_id_and_vni((u8 *)&cfg->info.key.tun_id, vni) &&
+		    ipv6_addr_equal(&addr6, &cfg->info.key.u.ipv6.dst))
 			return node->geneve;
 	}
 	return NULL;
@@ -386,11 +391,6 @@ static int geneve_init(struct net_device *dev)
 	if (err)
 		return err;

-	err = dst_cache_init(&geneve->cfg.info.dst_cache, GFP_KERNEL);
-	if (err) {
-		gro_cells_destroy(&geneve->gro_cells);
-		return err;
-	}
 	netdev_lockdep_set_classes(dev);
 	return 0;
 }
@@ -399,7 +399,6 @@ static void geneve_uninit(struct net_device *dev)
 {
 	struct geneve_dev *geneve = netdev_priv(dev);

-	dst_cache_destroy(&geneve->cfg.info.dst_cache);
 	gro_cells_destroy(&geneve->gro_cells);
 }

@@ -650,6 +649,7 @@ static int geneve_post_decap_hint(const struct sock *sk, struct sk_buff *skb,
 /* Callback from net/ipv4/udp.c to receive packets */
 static int geneve_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
 {
+	const struct geneve_config *cfg;
 	struct genevehdr *geneveh;
 	struct geneve_dev *geneve;
 	struct geneve_sock *gs;
@@ -675,8 +675,9 @@ static int geneve_udp_encap_recv(struct sock *sk, struct sk_buff *skb)

 	inner_proto = geneveh->proto_type;

-	if (unlikely((!geneve->cfg.inner_proto_inherit &&
-		      inner_proto != htons(ETH_P_TEB)))) {
+	cfg = rcu_dereference(geneve->cfg);
+	if (unlikely(!cfg || (!cfg->inner_proto_inherit &&
+			      inner_proto != htons(ETH_P_TEB)))) {
 		dev_dstats_rx_dropped(geneve->dev);
 		goto drop;
 	}
@@ -762,9 +763,10 @@ static int geneve_udp_encap_err_lookup(struct sock *sk, struct sk_buff *skb)
 }

 static struct sock *geneve_create_sock(struct net *net,
-				       struct geneve_dev *geneve, bool ipv6)
+				       struct geneve_dev *geneve,
+				       const struct geneve_config *cfg, bool ipv6)
 {
-	struct ip_tunnel_info *info = &geneve->cfg.info;
+	const struct ip_tunnel_info *info = &cfg->info;
 	struct udp_port_cfg udp_conf;
 	struct socket *sock;
 	int err;
@@ -775,7 +777,7 @@ static struct sock *geneve_create_sock(struct net *net,
 	if (ipv6) {
 		udp_conf.family = AF_INET6;
 		udp_conf.ipv6_v6only = 1;
-		udp_conf.use_udp6_rx_checksums = geneve->cfg.use_udp6_rx_checksums;
+		udp_conf.use_udp6_rx_checksums = cfg->use_udp6_rx_checksums;
 		udp_conf.local_ip6 = info->key.u.ipv6.src;
 	} else
 #endif
@@ -991,7 +993,8 @@ static int geneve_gro_complete(struct sock *sk, struct sk_buff *skb,

 /* Create new listen socket if needed */
 static struct geneve_sock *geneve_socket_create(struct net *net,
-						struct geneve_dev *geneve, bool ipv6)
+						struct geneve_dev *geneve,
+						const struct geneve_config *cfg, bool ipv6)
 {
 	struct geneve_net *gn = net_generic(net, geneve_net_id);
 	struct udp_tunnel_sock_cfg tunnel_cfg;
@@ -1003,7 +1006,7 @@ static struct geneve_sock *geneve_socket_create(struct net *net,
 	if (!gs)
 		return ERR_PTR(-ENOMEM);

-	sk = geneve_create_sock(net, geneve, ipv6);
+	sk = geneve_create_sock(net, geneve, cfg, ipv6);
 	if (IS_ERR(sk)) {
 		kfree(gs);
 		return ERR_CAST(sk);
@@ -1060,12 +1063,13 @@ static void geneve_sock_release(struct geneve_dev *geneve)
 }

 static struct geneve_sock *geneve_find_sock(struct net *net,
-					    struct geneve_dev *geneve, bool ipv6)
+					    struct geneve_dev *geneve,
+					    const struct geneve_config *cfg, bool ipv6)
 {
 	struct geneve_net *gn = net_generic(net, geneve_net_id);
-	struct ip_tunnel_info *info = &geneve->cfg.info;
+	const struct ip_tunnel_info *info = &cfg->info;
 	sa_family_t family = ipv6 ? AF_INET6 : AF_INET;
-	bool gro_hint = geneve->cfg.gro_hint;
+	bool gro_hint = cfg->gro_hint;
 	__be16 dst_port = info->key.tp_dst;
 	struct geneve_sock *gs;

@@ -1095,7 +1099,8 @@ static struct geneve_sock *geneve_find_sock(struct net *net,
 	return NULL;
 }

-static int geneve_sock_add(struct geneve_dev *geneve, bool ipv6)
+static int geneve_sock_add(struct geneve_dev *geneve,
+			   const struct geneve_config *cfg, bool ipv6)
 {
 	struct net *net = geneve->net;
 	struct geneve_dev_node *node;
@@ -1103,19 +1108,19 @@ static int geneve_sock_add(struct geneve_dev *geneve, bool ipv6)
 	__u8 vni[3];
 	__u32 hash;

-	gs = geneve_find_sock(net, geneve, ipv6);
+	gs = geneve_find_sock(net, geneve, cfg, ipv6);
 	if (gs) {
 		gs->refcnt++;
 		goto out;
 	}

-	gs = geneve_socket_create(net, geneve, ipv6);
+	gs = geneve_socket_create(net, geneve, cfg, ipv6);
 	if (IS_ERR(gs))
 		return PTR_ERR(gs);

 out:
-	gs->collect_md = geneve->cfg.collect_md;
-	gs->gro_hint = geneve->cfg.gro_hint;
+	gs->collect_md = cfg->collect_md;
+	gs->gro_hint = cfg->gro_hint;
 #if IS_ENABLED(CONFIG_IPV6)
 	if (ipv6) {
 		rcu_assign_pointer(geneve->sock6, gs);
@@ -1128,7 +1133,7 @@ static int geneve_sock_add(struct geneve_dev *geneve, bool ipv6)
 	}
 	node->geneve = geneve;

-	tunnel_id_to_vni(geneve->cfg.info.key.tun_id, vni);
+	tunnel_id_to_vni(cfg->info.key.tun_id, vni);
 	hash = geneve_net_vni_hash(vni);
 	hlist_add_head_rcu(&node->hlist, &gs->vni_list[hash]);
 	return 0;
@@ -1137,21 +1142,23 @@ static int geneve_sock_add(struct geneve_dev *geneve, bool ipv6)
 static int geneve_open(struct net_device *dev)
 {
 	struct geneve_dev *geneve = netdev_priv(dev);
-	bool dualstack = geneve->cfg.dualstack;
-	bool ipv4, ipv6;
+	const struct geneve_config *cfg;
+	bool ipv4, ipv6, dualstack;
 	int ret = 0;

-	ipv6 = geneve->cfg.info.mode & IP_TUNNEL_INFO_IPV6 || dualstack;
+	cfg = rtnl_dereference(geneve->cfg);
+	dualstack = cfg->dualstack;
+	ipv6 = cfg->info.mode & IP_TUNNEL_INFO_IPV6 || dualstack;
 	ipv4 = !ipv6 || dualstack;
 #if IS_ENABLED(CONFIG_IPV6)
 	if (ipv6) {
-		ret = geneve_sock_add(geneve, true);
+		ret = geneve_sock_add(geneve, cfg, true);
 		if (ret < 0 && ret != -EAFNOSUPPORT)
 			ipv4 = false;
 	}
 #endif
 	if (ipv4)
-		ret = geneve_sock_add(geneve, false);
+		ret = geneve_sock_add(geneve, cfg, false);
 	if (ret < 0)
 		geneve_sock_release(geneve);

@@ -1189,6 +1196,7 @@ static void geneve_build_header(struct genevehdr *geneveh,
 }

 static int geneve_build_gro_hint_opt(const struct geneve_dev *geneve,
+				     const struct geneve_config *cfg,
 				     struct sk_buff *skb)
 {
 	struct geneve_skb_cb *cb = GENEVE_SKB_CB(skb);
@@ -1201,7 +1209,7 @@ static int geneve_build_gro_hint_opt(const struct geneve_dev *geneve,
 	cb->gro_hint_len = 0;

 	/* Try to add the GRO hint only in case of double encap. */
-	if (!geneve->cfg.gro_hint || !skb->encapsulation)
+	if (!cfg->gro_hint || !skb->encapsulation)
 		return 0;

 	/*
@@ -1262,10 +1270,11 @@ static void geneve_put_gro_hint_opt(struct genevehdr *gnvh, int opt_size,

 static int geneve_build_skb(struct dst_entry *dst, struct sk_buff *skb,
 			    const struct ip_tunnel_info *info,
-			    const struct geneve_dev *geneve, int ip_hdr_len)
+			    const struct geneve_dev *geneve,
+			    const struct geneve_config *cfg, int ip_hdr_len)
 {
 	bool udp_sum = test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags);
-	bool inner_proto_inherit = geneve->cfg.inner_proto_inherit;
+	bool inner_proto_inherit = cfg->inner_proto_inherit;
 	bool xnet = !net_eq(geneve->net, dev_net(geneve->dev));
 	struct geneve_skb_cb *cb = GENEVE_SKB_CB(skb);
 	struct genevehdr *gnvh;
@@ -1306,14 +1315,14 @@ static int geneve_build_skb(struct dst_entry *dst, struct sk_buff *skb,
 }

 static u8 geneve_get_dsfield(struct sk_buff *skb, struct net_device *dev,
+			     const struct geneve_config *cfg,
 			     const struct ip_tunnel_info *info,
 			     bool *use_cache)
 {
-	struct geneve_dev *geneve = netdev_priv(dev);
 	u8 dsfield;

 	dsfield = info->key.tos;
-	if (dsfield == 1 && !geneve->cfg.collect_md) {
+	if (cfg && dsfield == 1 && !cfg->collect_md) {
 		dsfield = ip_tunnel_get_dsfield(ip_hdr(skb), skb);
 		*use_cache = false;
 	}
@@ -1323,6 +1332,7 @@ static u8 geneve_get_dsfield(struct sk_buff *skb, struct net_device *dev,

 static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 			   struct geneve_dev *geneve,
+			   const struct geneve_config *cfg,
 			   const struct ip_tunnel_info *info)
 {
 	struct geneve_sock *gs4 = rcu_dereference(geneve->sock4);
@@ -1335,35 +1345,35 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 	__be16 sport;
 	int err;

-	if (skb_vlan_inet_prepare(skb, geneve->cfg.inner_proto_inherit))
+	if (skb_vlan_inet_prepare(skb, cfg->inner_proto_inherit))
 		return -EINVAL;

 	if (!gs4)
 		return -EIO;

 	use_cache = ip_tunnel_dst_cache_usable(skb, info);
-	tos = geneve_get_dsfield(skb, dev, info, &use_cache);
+	tos = geneve_get_dsfield(skb, dev, cfg, info, &use_cache);
 	sport = udp_flow_src_port(geneve->net, skb,
-				  geneve->cfg.port_min,
-				  geneve->cfg.port_max, true);
+				  cfg->port_min,
+				  cfg->port_max, true);

 	rt = udp_tunnel_dst_lookup(skb, dev, geneve->net, 0, &saddr,
 				   &info->key,
-				   sport, geneve->cfg.info.key.tp_dst, tos,
+				   sport, cfg->info.key.tp_dst, tos,
 				   use_cache ?
 				   (struct dst_cache *)&info->dst_cache : NULL);
 	if (IS_ERR(rt))
 		return PTR_ERR(rt);

-	if (geneve->cfg.info.key.u.ipv4.src &&
-	    saddr != geneve->cfg.info.key.u.ipv4.src) {
+	if (cfg->info.key.u.ipv4.src &&
+	    saddr != cfg->info.key.u.ipv4.src) {
 		dst_release(&rt->dst);
 		return -EADDRNOTAVAIL;
 	}

 	err = skb_tunnel_check_pmtu(skb, &rt->dst,
 				    GENEVE_IPV4_HLEN + info->options_len +
-				    geneve_build_gro_hint_opt(geneve, skb),
+				    geneve_build_gro_hint_opt(geneve, cfg, skb),
 				    netif_is_any_bridge_port(dev));
 	if (err < 0) {
 		dst_release(&rt->dst);
@@ -1397,21 +1407,21 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 	}

 	tos = ip_tunnel_ecn_encap(tos, ip_hdr(skb), skb);
-	if (geneve->cfg.collect_md) {
+	if (cfg->collect_md) {
 		ttl = key->ttl;

 		df = test_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, key->tun_flags) ?
 		     htons(IP_DF) : 0;
 	} else {
-		if (geneve->cfg.ttl_inherit)
+		if (cfg->ttl_inherit)
 			ttl = ip_tunnel_get_ttl(ip_hdr(skb), skb);
 		else
 			ttl = key->ttl;
 		ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);

-		if (geneve->cfg.df == GENEVE_DF_SET) {
+		if (cfg->df == GENEVE_DF_SET) {
 			df = htons(IP_DF);
-		} else if (geneve->cfg.df == GENEVE_DF_INHERIT) {
+		} else if (cfg->df == GENEVE_DF_INHERIT) {
 			struct ethhdr *eth = skb_eth_hdr(skb);

 			if (ntohs(eth->h_proto) == ETH_P_IPV6) {
@@ -1425,13 +1435,13 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 		}
 	}

-	err = geneve_build_skb(&rt->dst, skb, info, geneve,
+	err = geneve_build_skb(&rt->dst, skb, info, geneve, cfg,
 			       sizeof(struct iphdr));
 	if (unlikely(err))
 		return err;

 	udp_tunnel_xmit_skb(rt, gs4->sk, skb, saddr, info->key.u.ipv4.dst,
-			    tos, ttl, df, sport, geneve->cfg.info.key.tp_dst,
+			    tos, ttl, df, sport, cfg->info.key.tp_dst,
 			    !net_eq(geneve->net, dev_net(geneve->dev)),
 			    !test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags),
 			    0);
@@ -1441,6 +1451,7 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 #if IS_ENABLED(CONFIG_IPV6)
 static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 			    struct geneve_dev *geneve,
+			    const struct geneve_config *cfg,
 			    const struct ip_tunnel_info *info)
 {
 	struct geneve_sock *gs6 = rcu_dereference(geneve->sock6);
@@ -1452,35 +1463,35 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 	__be16 sport;
 	int err;

-	if (skb_vlan_inet_prepare(skb, geneve->cfg.inner_proto_inherit))
+	if (skb_vlan_inet_prepare(skb, cfg->inner_proto_inherit))
 		return -EINVAL;

 	if (!gs6)
 		return -EIO;

 	use_cache = ip_tunnel_dst_cache_usable(skb, info);
-	prio = geneve_get_dsfield(skb, dev, info, &use_cache);
+	prio = geneve_get_dsfield(skb, dev, cfg, info, &use_cache);
 	sport = udp_flow_src_port(geneve->net, skb,
-				  geneve->cfg.port_min,
-				  geneve->cfg.port_max, true);
+				  cfg->port_min,
+				  cfg->port_max, true);

 	dst = udp_tunnel6_dst_lookup(skb, dev, geneve->net, gs6->sk, 0,
 				     &saddr, key, sport,
-				     geneve->cfg.info.key.tp_dst, prio,
+				     cfg->info.key.tp_dst, prio,
 				     use_cache ?
 				     (struct dst_cache *)&info->dst_cache : NULL);
 	if (IS_ERR(dst))
 		return PTR_ERR(dst);

-	if (!ipv6_addr_any(&geneve->cfg.info.key.u.ipv6.src) &&
-	    !ipv6_addr_equal(&saddr, &geneve->cfg.info.key.u.ipv6.src)) {
+	if (!ipv6_addr_any(&cfg->info.key.u.ipv6.src) &&
+	    !ipv6_addr_equal(&saddr, &cfg->info.key.u.ipv6.src)) {
 		dst_release(dst);
 		return -EADDRNOTAVAIL;
 	}

 	err = skb_tunnel_check_pmtu(skb, dst,
 				    GENEVE_IPV6_HLEN + info->options_len +
-				    geneve_build_gro_hint_opt(geneve, skb),
+				    geneve_build_gro_hint_opt(geneve, cfg, skb),
 				    netif_is_any_bridge_port(dev));
 	if (err < 0) {
 		dst_release(dst);
@@ -1513,22 +1524,22 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 	}

 	prio = ip_tunnel_ecn_encap(prio, ip_hdr(skb), skb);
-	if (geneve->cfg.collect_md) {
+	if (cfg->collect_md) {
 		ttl = key->ttl;
 	} else {
-		if (geneve->cfg.ttl_inherit)
+		if (cfg->ttl_inherit)
 			ttl = ip_tunnel_get_ttl(ip_hdr(skb), skb);
 		else
 			ttl = key->ttl;
 		ttl = ttl ? : ip6_dst_hoplimit(dst);
 	}
-	err = geneve_build_skb(dst, skb, info, geneve, sizeof(struct ipv6hdr));
+	err = geneve_build_skb(dst, skb, info, geneve, cfg, sizeof(struct ipv6hdr));
 	if (unlikely(err))
 		return err;

 	udp_tunnel6_xmit_skb(dst, gs6->sk, skb, dev,
 			     &saddr, &key->u.ipv6.dst, prio, ttl,
-			     info->key.label, sport, geneve->cfg.info.key.tp_dst,
+			     info->key.label, sport, cfg->info.key.tp_dst,
 			     !test_bit(IP_TUNNEL_CSUM_BIT,
 				       info->key.tun_flags),
 			     0);
@@ -1539,28 +1550,31 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct geneve_dev *geneve = netdev_priv(dev);
-	struct ip_tunnel_info *info = NULL;
+	const struct ip_tunnel_info *info = NULL;
+	const struct geneve_config *cfg;
 	int err;

-	if (geneve->cfg.collect_md) {
+	rcu_read_lock();
+	cfg = rcu_dereference(geneve->cfg);
+	if (cfg->collect_md) {
 		info = skb_tunnel_info(skb);
 		if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
 			netdev_dbg(dev, "no tunnel metadata\n");
 			dev_kfree_skb(skb);
 			dev_dstats_tx_dropped(dev);
+			rcu_read_unlock();
 			return NETDEV_TX_OK;
 		}
 	} else {
-		info = &geneve->cfg.info;
+		info = &cfg->info;
 	}

-	rcu_read_lock();
 #if IS_ENABLED(CONFIG_IPV6)
 	if (info->mode & IP_TUNNEL_INFO_IPV6)
-		err = geneve6_xmit_skb(skb, dev, geneve, info);
+		err = geneve6_xmit_skb(skb, dev, geneve, cfg, info);
 	else
 #endif
-		err = geneve_xmit_skb(skb, dev, geneve, info);
+		err = geneve_xmit_skb(skb, dev, geneve, cfg, info);
 	rcu_read_unlock();

 	if (likely(!err))
@@ -1593,8 +1607,13 @@ static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
 {
 	struct ip_tunnel_info *info = skb_tunnel_info(skb);
 	struct geneve_dev *geneve = netdev_priv(dev);
+	const struct geneve_config *cfg;
 	__be16 sport;

+	cfg = rcu_dereference(geneve->cfg);
+	if (unlikely(!cfg))
+		return -ENODEV;
+
 	if (ip_tunnel_info_af(info) == AF_INET) {
 		struct rtable *rt;
 		struct geneve_sock *gs4 = rcu_dereference(geneve->sock4);
@@ -1606,14 +1625,14 @@ static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
 			return -EIO;

 		use_cache = ip_tunnel_dst_cache_usable(skb, info);
-		tos = geneve_get_dsfield(skb, dev, info, &use_cache);
+		tos = geneve_get_dsfield(skb, dev, cfg, info, &use_cache);
 		sport = udp_flow_src_port(geneve->net, skb,
-					  geneve->cfg.port_min,
-					  geneve->cfg.port_max, true);
+					  cfg->port_min,
+					  cfg->port_max, true);

 		rt = udp_tunnel_dst_lookup(skb, dev, geneve->net, 0, &saddr,
 					   &info->key,
-					   sport, geneve->cfg.info.key.tp_dst,
+					   sport, cfg->info.key.tp_dst,
 					   tos,
 					   use_cache ? &info->dst_cache : NULL);
 		if (IS_ERR(rt))
@@ -1633,14 +1652,14 @@ static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
 			return -EIO;

 		use_cache = ip_tunnel_dst_cache_usable(skb, info);
-		prio = geneve_get_dsfield(skb, dev, info, &use_cache);
+		prio = geneve_get_dsfield(skb, dev, cfg, info, &use_cache);
 		sport = udp_flow_src_port(geneve->net, skb,
-					  geneve->cfg.port_min,
-					  geneve->cfg.port_max, true);
+					  cfg->port_min,
+					  cfg->port_max, true);

 		dst = udp_tunnel6_dst_lookup(skb, dev, geneve->net, gs6->sk, 0,
 					     &saddr, &info->key, sport,
-					     geneve->cfg.info.key.tp_dst, prio,
+					     cfg->info.key.tp_dst, prio,
 					     use_cache ? &info->dst_cache : NULL);
 		if (IS_ERR(dst))
 			return PTR_ERR(dst);
@@ -1653,7 +1672,7 @@ static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
 	}

 	info->key.tp_src = sport;
-	info->key.tp_dst = geneve->cfg.info.key.tp_dst;
+	info->key.tp_dst = cfg->info.key.tp_dst;
 	return 0;
 }

@@ -1709,7 +1728,50 @@ static void geneve_offload_rx_ports(struct net_device *dev, bool push)
 	}
 }

+static struct geneve_config *geneve_config_alloc(const struct geneve_config *src)
+{
+	struct geneve_config *cfg;
+	int err;
+
+	cfg = kmemdup(src, sizeof(*src), GFP_KERNEL);
+	if (!cfg)
+		return ERR_PTR(-ENOMEM);
+
+	cfg->info.dst_cache.cache = NULL;
+	err = dst_cache_init(&cfg->info.dst_cache, GFP_KERNEL);
+	if (err) {
+		kfree(cfg);
+		return ERR_PTR(err);
+	}
+
+	return cfg;
+}
+
+static void geneve_config_free(struct geneve_config *cfg)
+{
+	if (cfg) {
+		dst_cache_destroy(&cfg->info.dst_cache);
+		kfree(cfg);
+	}
+}
+
+static void geneve_config_free_rcu(struct rcu_head *head)
+{
+	struct geneve_config *cfg = container_of(head, struct geneve_config, rcu);
+
+	geneve_config_free(cfg);
+}
+
 /* Initialize the device structure. */
+static void geneve_free_dev(struct net_device *dev)
+{
+	struct geneve_dev *geneve = netdev_priv(dev);
+	struct geneve_config *cfg = rcu_dereference_protected(geneve->cfg, 1);
+
+	geneve_config_free(cfg);
+	RCU_INIT_POINTER(geneve->cfg, NULL);
+}
+
 static void geneve_setup(struct net_device *dev)
 {
 	ether_setup(dev);
@@ -1717,6 +1779,7 @@ static void geneve_setup(struct net_device *dev)
 	dev->netdev_ops = &geneve_netdev_ops;
 	dev->ethtool_ops = &geneve_ethtool_ops;
 	dev->needs_free_netdev = true;
+	dev->priv_destructor = geneve_free_dev;

 	SET_NETDEV_DEVTYPE(dev, &geneve_type);

@@ -1878,15 +1941,17 @@ static struct geneve_dev *geneve_find_dev(struct geneve_net *gn,
 	*tun_on_same_port = false;
 	*tun_collect_md = false;
 	list_for_each_entry(geneve, &gn->geneve_list, next) {
-		if (info->key.tp_dst == geneve->cfg.info.key.tp_dst &&
-		    (cfg->dualstack || geneve->cfg.dualstack ||
-		     geneve_saddr_conflict(info, &geneve->cfg.info))) {
-			*tun_collect_md |= geneve->cfg.collect_md;
+		const struct geneve_config *gcfg = rtnl_dereference(geneve->cfg);
+
+		if (info->key.tp_dst == gcfg->info.key.tp_dst &&
+		    (cfg->dualstack || gcfg->dualstack ||
+		     geneve_saddr_conflict(info, &gcfg->info))) {
+			*tun_collect_md |= gcfg->collect_md;
 			*tun_on_same_port = true;
 		}
-		if (info->key.tun_id == geneve->cfg.info.key.tun_id &&
-		    info->key.tp_dst == geneve->cfg.info.key.tp_dst &&
-		    !memcmp(&info->key.u, &geneve->cfg.info.key.u, sizeof(info->key.u)))
+		if (info->key.tun_id == gcfg->info.key.tun_id &&
+		    info->key.tp_dst == gcfg->info.key.tp_dst &&
+		    !memcmp(&info->key.u, &gcfg->info.key.u, sizeof(info->key.u)))
 			t = geneve;
 	}
 	return t;
@@ -1922,6 +1987,7 @@ static int geneve_configure(struct net *net, struct net_device *dev,
 	struct geneve_dev *t, *geneve = netdev_priv(dev);
 	const struct ip_tunnel_info *info = &cfg->info;
 	bool tun_collect_md, tun_on_same_port;
+	struct geneve_config *new_cfg;
 	int err, encap_len;

 	if (cfg->collect_md && !is_tnl_info_zero(info)) {
@@ -1962,10 +2028,13 @@ static int geneve_configure(struct net *net, struct net_device *dev,
 		}
 	}

-	dst_cache_reset(&geneve->cfg.info.dst_cache);
-	memcpy(&geneve->cfg, cfg, sizeof(*cfg));
+	new_cfg = geneve_config_alloc(cfg);
+	if (IS_ERR(new_cfg))
+		return PTR_ERR(new_cfg);

-	if (geneve->cfg.inner_proto_inherit) {
+	rcu_assign_pointer(geneve->cfg, new_cfg);
+
+	if (cfg->inner_proto_inherit) {
 		dev->header_ops = NULL;
 		dev->type = ARPHRD_NONE;
 		dev->hard_header_len = 0;
@@ -2323,81 +2392,45 @@ static int geneve_newlink(struct net_device *dev,
 	return 0;
 }

-/* Quiesces the geneve device data path for both TX and RX.
- *
- * On transmit geneve checks for non-NULL geneve_sock before it proceeds.
- * So, if we set that socket to NULL under RCU and wait for synchronize_net()
- * to complete for the existing set of in-flight packets to be transmitted,
- * then we would have quiesced the transmit data path. All the future packets
- * will get dropped until we unquiesce the data path.
- *
- * On receive geneve dereference the geneve_sock stashed in the socket. So,
- * if we set that to NULL under RCU and wait for synchronize_net() to
- * complete, then we would have quiesced the receive data path.
+/* Update the device configuration under RTNL.
+ * We use RCU swap to update the configuration atomically, so the data path
+ * (both TX and RX) can continue running without interruption or packet loss.
 */
-static void geneve_quiesce(struct geneve_dev *geneve, struct geneve_sock **gs4,
-			   struct geneve_sock **gs6)
-{
-	*gs4 = rtnl_dereference(geneve->sock4);
-	rcu_assign_pointer(geneve->sock4, NULL);
-	if (*gs4)
-		rcu_assign_sk_user_data((*gs4)->sk, NULL);
-#if IS_ENABLED(CONFIG_IPV6)
-	*gs6 = rtnl_dereference(geneve->sock6);
-	rcu_assign_pointer(geneve->sock6, NULL);
-	if (*gs6)
-		rcu_assign_sk_user_data((*gs6)->sk, NULL);
-#else
-	*gs6 = NULL;
-#endif
-	synchronize_net();
-}
-
-/* Resumes the geneve device data path for both TX and RX. */
-static void geneve_unquiesce(struct geneve_dev *geneve, struct geneve_sock *gs4,
-			     struct geneve_sock __maybe_unused *gs6)
-{
-	rcu_assign_pointer(geneve->sock4, gs4);
-	if (gs4)
-		rcu_assign_sk_user_data(gs4->sk, gs4);
-#if IS_ENABLED(CONFIG_IPV6)
-	rcu_assign_pointer(geneve->sock6, gs6);
-	if (gs6)
-		rcu_assign_sk_user_data(gs6->sk, gs6);
-#endif
-}
-
 static int geneve_changelink(struct net_device *dev, struct nlattr *tb[],
 			     struct nlattr *data[],
 			     struct netlink_ext_ack *extack)
 {
 	struct geneve_dev *geneve = netdev_priv(dev);
-	struct geneve_sock *gs4, *gs6;
-	struct geneve_config cfg;
+	struct geneve_config *old_cfg = rtnl_dereference(geneve->cfg);
+	struct geneve_config *cfg;
 	int err;

 	/* If the geneve device is configured for metadata (or externally
 	 * controlled, for example, OVS), then nothing can be changed.
 	 */
-	if (geneve->cfg.collect_md)
+	if (old_cfg->collect_md)
 		return -EOPNOTSUPP;

 	/* Start with the existing info. */
-	memcpy(&cfg, &geneve->cfg, sizeof(cfg));
-	err = geneve_nl2info(tb, data, extack, &cfg, true);
+	cfg = geneve_config_alloc(old_cfg);
+	if (IS_ERR(cfg))
+		return PTR_ERR(cfg);
+
+	err = geneve_nl2info(tb, data, extack, cfg, true);
 	if (err)
-		return err;
+		goto err_free_cfg;

-	if (!geneve_dst_addr_equal(&geneve->cfg.info, &cfg.info)) {
-		dst_cache_reset(&cfg.info.dst_cache);
-		geneve_link_config(dev, &cfg.info, tb);
-	}
+	if (!geneve_dst_addr_equal(&old_cfg->info, &cfg->info))
+		geneve_link_config(dev, &cfg->info, tb);

-	geneve_quiesce(geneve, &gs4, &gs6);
-	memcpy(&geneve->cfg, &cfg, sizeof(cfg));
-	geneve_unquiesce(geneve, gs4, gs6);
+	rcu_assign_pointer(geneve->cfg, cfg);

+	call_rcu_hurry(&old_cfg->rcu, geneve_config_free_rcu);
 	return 0;
+
+err_free_cfg:
+	geneve_config_free(cfg);
+	return err;
 }

 static void geneve_dellink(struct net_device *dev, struct list_head *head)
@@ -2431,16 +2464,27 @@ static size_t geneve_get_size(const struct net_device *dev)

 static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
 {
-	struct geneve_dev *geneve = netdev_priv(dev);
-	struct ip_tunnel_info *info = &geneve->cfg.info;
-	bool ttl_inherit = geneve->cfg.ttl_inherit;
-	bool metadata = geneve->cfg.collect_md;
-	struct ifla_geneve_port_range ports = {
-		.low	= htons(geneve->cfg.port_min),
-		.high	= htons(geneve->cfg.port_max),
-	};
+	const struct geneve_dev *geneve = netdev_priv(dev);
+	struct ifla_geneve_port_range ports;
+	const struct geneve_config *cfg;
+	const struct ip_tunnel_info *info;
+	bool ttl_inherit, metadata;
 	__u8 tmp_vni[3];
 	__u32 vni;
+	int err = 0;
+
+	rcu_read_lock();
+	cfg = rcu_dereference(geneve->cfg);
+	if (!cfg) {
+		err = -ENODEV;
+		goto out;
+	}
+
+	info = &cfg->info;
+	ttl_inherit = cfg->ttl_inherit;
+	metadata = cfg->collect_md;
+	ports.low = htons(cfg->port_min);
+	ports.high = htons(cfg->port_max);

 	tunnel_id_to_vni(info->key.tun_id, tmp_vni);
 	vni = (tmp_vni[0] << 16) | (tmp_vni[1] << 8) | tmp_vni[2];
@@ -2468,17 +2512,17 @@ static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
 #endif
 	}

-	if (!geneve->cfg.dualstack) {
+	if (!cfg->dualstack) {
 		if (ip_tunnel_info_af(info) == AF_INET) {
 			if ((info->key.u.ipv4.src ||
-			     geneve->cfg.collect_md) &&
+			     metadata) &&
 			    nla_put_in_addr(skb, IFLA_GENEVE_LOCAL,
 					    info->key.u.ipv4.src))
 				goto nla_put_failure;
 #if IS_ENABLED(CONFIG_IPV6)
 		} else {
 			if ((!ipv6_addr_any(&info->key.u.ipv6.src) ||
-			     geneve->cfg.collect_md) &&
+			     metadata) &&
 			    nla_put_in6_addr(skb, IFLA_GENEVE_LOCAL6,
 					     &info->key.u.ipv6.src))
 				goto nla_put_failure;
@@ -2491,7 +2535,7 @@ static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	    nla_put_be32(skb, IFLA_GENEVE_LABEL, info->key.label))
 		goto nla_put_failure;

-	if (nla_put_u8(skb, IFLA_GENEVE_DF, geneve->cfg.df))
+	if (nla_put_u8(skb, IFLA_GENEVE_DF, cfg->df))
 		goto nla_put_failure;

 	if (nla_put_be16(skb, IFLA_GENEVE_PORT, info->key.tp_dst))
@@ -2502,28 +2546,31 @@ static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)

 #if IS_ENABLED(CONFIG_IPV6)
 	if (nla_put_u8(skb, IFLA_GENEVE_UDP_ZERO_CSUM6_RX,
-		       !geneve->cfg.use_udp6_rx_checksums))
+		       !cfg->use_udp6_rx_checksums))
 		goto nla_put_failure;
 #endif

 	if (nla_put_u8(skb, IFLA_GENEVE_TTL_INHERIT, ttl_inherit))
 		goto nla_put_failure;

-	if (geneve->cfg.inner_proto_inherit &&
+	if (cfg->inner_proto_inherit &&
 	    nla_put_flag(skb, IFLA_GENEVE_INNER_PROTO_INHERIT))
 		goto nla_put_failure;

 	if (nla_put(skb, IFLA_GENEVE_PORT_RANGE, sizeof(ports), &ports))
 		goto nla_put_failure;

-	if (geneve->cfg.gro_hint &&
+	if (cfg->gro_hint &&
 	    nla_put_flag(skb, IFLA_GENEVE_GRO_HINT))
 		goto nla_put_failure;

-	return 0;
+out:
+	rcu_read_unlock();
+	return err;

 nla_put_failure:
-	return -EMSGSIZE;
+	err = -EMSGSIZE;
+	goto out;
 }

 static struct rtnl_link_ops geneve_link_ops __read_mostly = {
@@ -2671,6 +2718,7 @@ static void __exit geneve_cleanup_module(void)
 	rtnl_link_unregister(&geneve_link_ops);
 	unregister_netdevice_notifier(&geneve_notifier_block);
 	unregister_pernet_subsys(&geneve_net_ops);
+	rcu_barrier();
 }
 module_exit(geneve_cleanup_module);