Merge branch 'net-remove-some-rcu_bh-cruft'

Eric Dumazet says:

====================
net: remove some rcu_bh cruft

There is no point using rcu_bh variant hoping to free objects faster,
especially hen using call_rcu() or kfree_rcu().

Disabling/enabling BH has a non-zero cost, and adds distracting
hot spots in kernel profiles eg. in ip6_xmit().
====================

Link: https://lore.kernel.org/r/20230321040115.787497-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

15 files changed, 114 insertions, 117 deletions

diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index 92ad75549e9c..f0c87baaf6c0 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -62,16 +62,6 @@ static inline bool lockdep_rtnl_is_held(void)
 	rcu_dereference_check(p, lockdep_rtnl_is_held())
 
 /**
- * rcu_dereference_bh_rtnl - rcu_dereference_bh with debug checking
- * @p: The pointer to read, prior to dereference
- *
- * Do an rcu_dereference_bh(p), but check caller either holds rcu_read_lock_bh()
- * or RTNL. Note : Please prefer rtnl_dereference() or rcu_dereference_bh()
- */
-#define rcu_dereference_bh_rtnl(p)				\
-	rcu_dereference_bh_check(p, lockdep_rtnl_is_held())
-
-/**
  * rtnl_dereference - fetch RCU pointer when updates are prevented by RTNL
  * @p: The pointer to read, prior to dereferencing
  *
diff --git a/include/net/arp.h b/include/net/arp.h
index d7ef4ec71dfe..e8747e0713c7 100644
--- a/include/net/arp.h
+++ b/include/net/arp.h
@@ -38,11 +38,11 @@ static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32
 {
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __ipv4_neigh_lookup_noref(dev, key);
 	if (n && !refcount_inc_not_zero(&n->refcnt))
 		n = NULL;
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	return n;
 }
@@ -51,10 +51,10 @@ static inline void __ipv4_confirm_neigh(struct net_device *dev, u32 key)
 {
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __ipv4_neigh_lookup_noref(dev, key);
 	neigh_confirm(n);
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 }
 
 void arp_init(void);
diff --git a/include/net/ndisc.h b/include/net/ndisc.h
index 07e5168cdaf9..52eae0943433 100644
--- a/include/net/ndisc.h
+++ b/include/net/ndisc.h
@@ -395,11 +395,11 @@ static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, cons
 {
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __ipv6_neigh_lookup_noref(dev, pkey);
 	if (n && !refcount_inc_not_zero(&n->refcnt))
 		n = NULL;
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	return n;
 }
@@ -409,10 +409,10 @@ static inline void __ipv6_confirm_neigh(struct net_device *dev,
 {
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __ipv6_neigh_lookup_noref(dev, pkey);
 	neigh_confirm(n);
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 }
 
 static inline void __ipv6_confirm_neigh_stub(struct net_device *dev,
@@ -420,10 +420,10 @@ static inline void __ipv6_confirm_neigh_stub(struct net_device *dev,
 {
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __ipv6_neigh_lookup_noref_stub(dev, pkey);
 	neigh_confirm(n);
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 }
 
 /* uses ipv6_stub and is meant for use outside of IPv6 core */
diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index c8d39bba2a0d..3fa5774bddac 100644
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -299,14 +299,14 @@ static inline struct neighbour *___neigh_lookup_noref(
 	const void *pkey,
 	struct net_device *dev)
 {
-	struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht);
+	struct neigh_hash_table *nht = rcu_dereference(tbl->nht);
 	struct neighbour *n;
 	u32 hash_val;
 
 	hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
-	for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
+	for (n = rcu_dereference(nht->hash_buckets[hash_val]);
 	     n != NULL;
-	     n = rcu_dereference_bh(n->next)) {
+	     n = rcu_dereference(n->next)) {
 		if (n->dev == dev && key_eq(n, pkey))
 			return n;
 	}
diff --git a/include/net/nexthop.h b/include/net/nexthop.h
index 28085b995ddc..9fa291a04621 100644
--- a/include/net/nexthop.h
+++ b/include/net/nexthop.h
@@ -498,7 +498,7 @@ static inline struct fib6_nh *nexthop_fib6_nh(struct nexthop *nh)
 }
 
 /* Variant of nexthop_fib6_nh().
- * Caller should either hold rcu_read_lock_bh(), or RTNL.
+ * Caller should either hold rcu_read_lock(), or RTNL.
  */
 static inline struct fib6_nh *nexthop_fib6_nh_bh(struct nexthop *nh)
 {
@@ -507,13 +507,13 @@ static inline struct fib6_nh *nexthop_fib6_nh_bh(struct nexthop *nh)
 	if (nh->is_group) {
 		struct nh_group *nh_grp;
 
-		nh_grp = rcu_dereference_bh_rtnl(nh->nh_grp);
+		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
 		nh = nexthop_mpath_select(nh_grp, 0);
 		if (!nh)
 			return NULL;
 	}
 
-	nhi = rcu_dereference_bh_rtnl(nh->nh_info);
+	nhi = rcu_dereference_rtnl(nh->nh_info);
 	if (nhi->family == AF_INET6)
 		return &nhi->fib6_nh;
 
diff --git a/net/core/filter.c b/net/core/filter.c
index d052fac28d02..a8c8fd96c822 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2204,7 +2204,7 @@ static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
 			return -ENOMEM;
 	}
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	if (!nh) {
 		dst = skb_dst(skb);
 		nexthop = rt6_nexthop(container_of(dst, struct rt6_info, dst),
@@ -2217,10 +2217,12 @@ static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
 		int ret;
 
 		sock_confirm_neigh(skb, neigh);
+		local_bh_disable();
 		dev_xmit_recursion_inc();
 		ret = neigh_output(neigh, skb, false);
 		dev_xmit_recursion_dec();
-		rcu_read_unlock_bh();
+		local_bh_enable();
+		rcu_read_unlock();
 		return ret;
 	}
 	rcu_read_unlock_bh();
@@ -2302,7 +2304,7 @@ static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
 			return -ENOMEM;
 	}
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	if (!nh) {
 		struct dst_entry *dst = skb_dst(skb);
 		struct rtable *rt = container_of(dst, struct rtable, dst);
@@ -2314,7 +2316,7 @@ static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
 	} else if (nh->nh_family == AF_INET) {
 		neigh = ip_neigh_gw4(dev, nh->ipv4_nh);
 	} else {
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 		goto out_drop;
 	}
 
@@ -2322,13 +2324,15 @@ static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
 		int ret;
 
 		sock_confirm_neigh(skb, neigh);
+		local_bh_disable();
 		dev_xmit_recursion_inc();
 		ret = neigh_output(neigh, skb, is_v6gw);
 		dev_xmit_recursion_dec();
-		rcu_read_unlock_bh();
+		local_bh_enable();
+		rcu_read_unlock();
 		return ret;
 	}
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 out_drop:
 	kfree_skb(skb);
 	return -ENETDOWN;
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 90d399b3f980..ddd0f32de20e 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -614,7 +614,7 @@ struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 
 	NEIGH_CACHE_STAT_INC(tbl, lookups);
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __neigh_lookup_noref(tbl, pkey, dev);
 	if (n) {
 		if (!refcount_inc_not_zero(&n->refcnt))
@@ -622,7 +622,7 @@ struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
 		NEIGH_CACHE_STAT_INC(tbl, hits);
 	}
 
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 	return n;
 }
 EXPORT_SYMBOL(neigh_lookup);
@@ -2184,11 +2184,11 @@ static int neightbl_fill_info(struct sk_buff *skb, struct neigh_table *tbl,
 			.ndtc_proxy_qlen	= tbl->proxy_queue.qlen,
 		};
 
-		rcu_read_lock_bh();
-		nht = rcu_dereference_bh(tbl->nht);
+		rcu_read_lock();
+		nht = rcu_dereference(tbl->nht);
 		ndc.ndtc_hash_rnd = nht->hash_rnd[0];
 		ndc.ndtc_hash_mask = ((1 << nht->hash_shift) - 1);
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 
 		if (nla_put(skb, NDTA_CONFIG, sizeof(ndc), &ndc))
 			goto nla_put_failure;
@@ -2703,15 +2703,15 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
 	if (filter->dev_idx || filter->master_idx)
 		flags |= NLM_F_DUMP_FILTERED;
 
-	rcu_read_lock_bh();
-	nht = rcu_dereference_bh(tbl->nht);
+	rcu_read_lock();
+	nht = rcu_dereference(tbl->nht);
 
 	for (h = s_h; h < (1 << nht->hash_shift); h++) {
 		if (h > s_h)
 			s_idx = 0;
-		for (n = rcu_dereference_bh(nht->hash_buckets[h]), idx = 0;
+		for (n = rcu_dereference(nht->hash_buckets[h]), idx = 0;
 		     n != NULL;
-		     n = rcu_dereference_bh(n->next)) {
+		     n = rcu_dereference(n->next)) {
 			if (idx < s_idx || !net_eq(dev_net(n->dev), net))
 				goto next;
 			if (neigh_ifindex_filtered(n->dev, filter->dev_idx) ||
@@ -2730,7 +2730,7 @@ next:
 	}
 	rc = skb->len;
 out:
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 	cb->args[1] = h;
 	cb->args[2] = idx;
 	return rc;
@@ -3075,20 +3075,20 @@ void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void
 	int chain;
 	struct neigh_hash_table *nht;
 
-	rcu_read_lock_bh();
-	nht = rcu_dereference_bh(tbl->nht);
+	rcu_read_lock();
+	nht = rcu_dereference(tbl->nht);
 
-	read_lock(&tbl->lock); /* avoid resizes */
+	read_lock_bh(&tbl->lock); /* avoid resizes */
 	for (chain = 0; chain < (1 << nht->hash_shift); chain++) {
 		struct neighbour *n;
 
-		for (n = rcu_dereference_bh(nht->hash_buckets[chain]);
+		for (n = rcu_dereference(nht->hash_buckets[chain]);
 		     n != NULL;
-		     n = rcu_dereference_bh(n->next))
+		     n = rcu_dereference(n->next))
 			cb(n, cookie);
 	}
-	read_unlock(&tbl->lock);
-	rcu_read_unlock_bh();
+	read_unlock_bh(&tbl->lock);
+	rcu_read_unlock();
 }
 EXPORT_SYMBOL(neigh_for_each);
 
@@ -3138,7 +3138,7 @@ int neigh_xmit(int index, struct net_device *dev,
 		tbl = neigh_tables[index];
 		if (!tbl)
 			goto out;
-		rcu_read_lock_bh();
+		rcu_read_lock();
 		if (index == NEIGH_ARP_TABLE) {
 			u32 key = *((u32 *)addr);
 
@@ -3150,11 +3150,11 @@ int neigh_xmit(int index, struct net_device *dev,
 			neigh = __neigh_create(tbl, addr, dev, false);
 		err = PTR_ERR(neigh);
 		if (IS_ERR(neigh)) {
-			rcu_read_unlock_bh();
+			rcu_read_unlock();
 			goto out_kfree_skb;
 		}
 		err = neigh->output(neigh, skb);
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 	}
 	else if (index == NEIGH_LINK_TABLE) {
 		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
@@ -3183,7 +3183,7 @@ static struct neighbour *neigh_get_first(struct seq_file *seq)
 
 	state->flags &= ~NEIGH_SEQ_IS_PNEIGH;
 	for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) {
-		n = rcu_dereference_bh(nht->hash_buckets[bucket]);
+		n = rcu_dereference(nht->hash_buckets[bucket]);
 
 		while (n) {
 			if (!net_eq(dev_net(n->dev), net))
@@ -3201,7 +3201,7 @@ static struct neighbour *neigh_get_first(struct seq_file *seq)
 			if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
 				break;
 next:
-			n = rcu_dereference_bh(n->next);
+			n = rcu_dereference(n->next);
 		}
 
 		if (n)
@@ -3225,7 +3225,7 @@ static struct neighbour *neigh_get_next(struct seq_file *seq,
 		if (v)
 			return n;
 	}
-	n = rcu_dereference_bh(n->next);
+	n = rcu_dereference(n->next);
 
 	while (1) {
 		while (n) {
@@ -3243,7 +3243,7 @@ static struct neighbour *neigh_get_next(struct seq_file *seq,
 			if (READ_ONCE(n->nud_state) & ~NUD_NOARP)
 				break;
 next:
-			n = rcu_dereference_bh(n->next);
+			n = rcu_dereference(n->next);
 		}
 
 		if (n)
@@ -3252,7 +3252,7 @@ next:
 		if (++state->bucket >= (1 << nht->hash_shift))
 			break;
 
-		n = rcu_dereference_bh(nht->hash_buckets[state->bucket]);
+		n = rcu_dereference(nht->hash_buckets[state->bucket]);
 	}
 
 	if (n && pos)
@@ -3354,7 +3354,7 @@ static void *neigh_get_idx_any(struct seq_file *seq, loff_t *pos)
 
 void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl, unsigned int neigh_seq_flags)
 	__acquires(tbl->lock)
-	__acquires(rcu_bh)
+	__acquires(rcu)
 {
 	struct neigh_seq_state *state = seq->private;
 
@@ -3362,9 +3362,9 @@ void *neigh_seq_start(struct seq_file *seq, loff_t *pos, struct neigh_table *tbl
 	state->bucket = 0;
 	state->flags = (neigh_seq_flags & ~NEIGH_SEQ_IS_PNEIGH);
 
-	rcu_read_lock_bh();
-	state->nht = rcu_dereference_bh(tbl->nht);
-	read_lock(&tbl->lock);
+	rcu_read_lock();
+	state->nht = rcu_dereference(tbl->nht);
+	read_lock_bh(&tbl->lock);
 
 	return *pos ? neigh_get_idx_any(seq, pos) : SEQ_START_TOKEN;
 }
@@ -3399,13 +3399,13 @@ EXPORT_SYMBOL(neigh_seq_next);
 
 void neigh_seq_stop(struct seq_file *seq, void *v)
 	__releases(tbl->lock)
-	__releases(rcu_bh)
+	__releases(rcu)
 {
 	struct neigh_seq_state *state = seq->private;
 	struct neigh_table *tbl = state->tbl;
 
-	read_unlock(&tbl->lock);
-	rcu_read_unlock_bh();
+	read_unlock_bh(&tbl->lock);
+	rcu_read_unlock();
 }
 EXPORT_SYMBOL(neigh_seq_stop);
 
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 574ff450c4d2..65ba18a91865 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -2191,7 +2191,7 @@ static bool fib_good_nh(const struct fib_nh *nh)
 	if (nh->fib_nh_scope == RT_SCOPE_LINK) {
 		struct neighbour *n;
 
-		rcu_read_lock_bh();
+		rcu_read_lock();
 
 		if (likely(nh->fib_nh_gw_family == AF_INET))
 			n = __ipv4_neigh_lookup_noref(nh->fib_nh_dev,
@@ -2204,7 +2204,7 @@ static bool fib_good_nh(const struct fib_nh *nh)
 		if (n)
 			state = READ_ONCE(n->nud_state);
 
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 	}
 
 	return !!(state & NUD_VALID);
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index cb04dbad9ea4..22a90a9392eb 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -219,7 +219,7 @@ static int ip_finish_output2(struct net *net, struct sock *sk, struct sk_buff *s
 			return res;
 	}
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
 	if (!IS_ERR(neigh)) {
 		int res;
@@ -227,10 +227,10 @@ static int ip_finish_output2(struct net *net, struct sock *sk, struct sk_buff *s
 		sock_confirm_neigh(skb, neigh);
 		/* if crossing protocols, can not use the cached header */
 		res = neigh_output(neigh, skb, is_v6gw);
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 		return res;
 	}
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	net_dbg_ratelimited("%s: No header cache and no neighbour!\n",
 			    __func__);
diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
index e28a99f1996b..f95142e56da0 100644
--- a/net/ipv4/nexthop.c
+++ b/net/ipv4/nexthop.c
@@ -1124,13 +1124,13 @@ static bool ipv6_good_nh(const struct fib6_nh *nh)
 	int state = NUD_REACHABLE;
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 
 	n = __ipv6_neigh_lookup_noref_stub(nh->fib_nh_dev, &nh->fib_nh_gw6);
 	if (n)
 		state = READ_ONCE(n->nud_state);
 
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	return !!(state & NUD_VALID);
 }
@@ -1140,14 +1140,14 @@ static bool ipv4_good_nh(const struct fib_nh *nh)
 	int state = NUD_REACHABLE;
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 
 	n = __ipv4_neigh_lookup_noref(nh->fib_nh_dev,
 				      (__force u32)nh->fib_nh_gw4);
 	if (n)
 		state = READ_ONCE(n->nud_state);
 
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	return !!(state & NUD_VALID);
 }
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 232009d216c4..6a0a0bb452e9 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -408,7 +408,7 @@ static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
 	struct net_device *dev = dst->dev;
 	struct neighbour *n;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 
 	if (likely(rt->rt_gw_family == AF_INET)) {
 		n = ip_neigh_gw4(dev, rt->rt_gw4);
@@ -424,7 +424,7 @@ static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
 	if (!IS_ERR(n) && !refcount_inc_not_zero(&n->refcnt))
 		n = NULL;
 
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	return n;
 }
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index faa47f9ea73a..31e0097878c5 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1034,7 +1034,7 @@ static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
 	int err = 0;
 
-	spin_lock(&net->ipv6.addrconf_hash_lock);
+	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
 
 	/* Ignore adding duplicate addresses on an interface */
 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
@@ -1044,7 +1044,7 @@ static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
 	}
 
-	spin_unlock(&net->ipv6.addrconf_hash_lock);
+	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
 
 	return err;
 }
@@ -1139,15 +1139,15 @@ ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
 	/* For caller */
 	refcount_set(&ifa->refcnt, 1);
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 
 	err = ipv6_add_addr_hash(idev->dev, ifa);
 	if (err < 0) {
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 		goto out;
 	}
 
-	write_lock(&idev->lock);
+	write_lock_bh(&idev->lock);
 
 	/* Add to inet6_dev unicast addr list. */
 	ipv6_link_dev_addr(idev, ifa);
@@ -1158,9 +1158,9 @@ ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
 	}
 
 	in6_ifa_hold(ifa);
-	write_unlock(&idev->lock);
+	write_unlock_bh(&idev->lock);
 
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
 out:
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index 18481eb76a0a..b3ca4beb4405 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -58,18 +58,18 @@ DEFINE_STATIC_KEY_DEFERRED_FALSE(ipv6_flowlabel_exclusive, HZ);
 EXPORT_SYMBOL(ipv6_flowlabel_exclusive);
 
 #define for_each_fl_rcu(hash, fl)				\
-	for (fl = rcu_dereference_bh(fl_ht[(hash)]);		\
+	for (fl = rcu_dereference(fl_ht[(hash)]);		\
 	     fl != NULL;					\
-	     fl = rcu_dereference_bh(fl->next))
+	     fl = rcu_dereference(fl->next))
 #define for_each_fl_continue_rcu(fl)				\
-	for (fl = rcu_dereference_bh(fl->next);			\
+	for (fl = rcu_dereference(fl->next);			\
 	     fl != NULL;					\
-	     fl = rcu_dereference_bh(fl->next))
+	     fl = rcu_dereference(fl->next))
 
 #define for_each_sk_fl_rcu(np, sfl)				\
-	for (sfl = rcu_dereference_bh(np->ipv6_fl_list);	\
+	for (sfl = rcu_dereference(np->ipv6_fl_list);	\
 	     sfl != NULL;					\
-	     sfl = rcu_dereference_bh(sfl->next))
+	     sfl = rcu_dereference(sfl->next))
 
 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
 {
@@ -86,11 +86,11 @@ static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
 {
 	struct ip6_flowlabel *fl;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	fl = __fl_lookup(net, label);
 	if (fl && !atomic_inc_not_zero(&fl->users))
 		fl = NULL;
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 	return fl;
 }
 
@@ -217,6 +217,7 @@ static struct ip6_flowlabel *fl_intern(struct net *net,
 
 	fl->label = label & IPV6_FLOWLABEL_MASK;
 
+	rcu_read_lock();
 	spin_lock_bh(&ip6_fl_lock);
 	if (label == 0) {
 		for (;;) {
@@ -240,6 +241,7 @@ static struct ip6_flowlabel *fl_intern(struct net *net,
 		if (lfl) {
 			atomic_inc(&lfl->users);
 			spin_unlock_bh(&ip6_fl_lock);
+			rcu_read_unlock();
 			return lfl;
 		}
 	}
@@ -249,6 +251,7 @@ static struct ip6_flowlabel *fl_intern(struct net *net,
 	rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl);
 	atomic_inc(&fl_size);
 	spin_unlock_bh(&ip6_fl_lock);
+	rcu_read_unlock();
 	return NULL;
 }
 
@@ -263,17 +266,17 @@ struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label)
 
 	label &= IPV6_FLOWLABEL_MASK;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	for_each_sk_fl_rcu(np, sfl) {
 		struct ip6_flowlabel *fl = sfl->fl;
 
 		if (fl->label == label && atomic_inc_not_zero(&fl->users)) {
 			fl->lastuse = jiffies;
-			rcu_read_unlock_bh();
+			rcu_read_unlock();
 			return fl;
 		}
 	}
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(__fl6_sock_lookup);
@@ -475,10 +478,10 @@ static int mem_check(struct sock *sk)
 	if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
 		return 0;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	for_each_sk_fl_rcu(np, sfl)
 		count++;
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	if (room <= 0 ||
 	    ((count >= FL_MAX_PER_SOCK ||
@@ -515,7 +518,7 @@ int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 		return 0;
 	}
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 
 	for_each_sk_fl_rcu(np, sfl) {
 		if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) {
@@ -527,11 +530,11 @@ int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 			freq->flr_linger = sfl->fl->linger / HZ;
 
 			spin_unlock_bh(&ip6_fl_lock);
-			rcu_read_unlock_bh();
+			rcu_read_unlock();
 			return 0;
 		}
 	}
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	return -ENOENT;
 }
@@ -581,16 +584,16 @@ static int ipv6_flowlabel_renew(struct sock *sk, struct in6_flowlabel_req *freq)
 	struct ipv6_fl_socklist *sfl;
 	int err;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	for_each_sk_fl_rcu(np, sfl) {
 		if (sfl->fl->label == freq->flr_label) {
 			err = fl6_renew(sfl->fl, freq->flr_linger,
 					freq->flr_expires);
-			rcu_read_unlock_bh();
+			rcu_read_unlock();
 			return err;
 		}
 	}
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	if (freq->flr_share == IPV6_FL_S_NONE &&
 	    ns_capable(net->user_ns, CAP_NET_ADMIN)) {
@@ -641,11 +644,11 @@ static int ipv6_flowlabel_get(struct sock *sk, struct in6_flowlabel_req *freq,
 
 	if (freq->flr_label) {
 		err = -EEXIST;
-		rcu_read_lock_bh();
+		rcu_read_lock();
 		for_each_sk_fl_rcu(np, sfl) {
 			if (sfl->fl->label == freq->flr_label) {
 				if (freq->flr_flags & IPV6_FL_F_EXCL) {
-					rcu_read_unlock_bh();
+					rcu_read_unlock();
 					goto done;
 				}
 				fl1 = sfl->fl;
@@ -654,7 +657,7 @@ static int ipv6_flowlabel_get(struct sock *sk, struct in6_flowlabel_req *freq,
 				break;
 			}
 		}
-		rcu_read_unlock_bh();
+		rcu_read_unlock();
 
 		if (!fl1)
 			fl1 = fl_lookup(net, freq->flr_label);
@@ -809,7 +812,7 @@ static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
 
 	state->pid_ns = proc_pid_ns(file_inode(seq->file)->i_sb);
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
 }
 
@@ -828,7 +831,7 @@ static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
 	__releases(RCU)
 {
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 }
 
 static int ip6fl_seq_show(struct seq_file *seq, void *v)
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index e5ed39a3c65f..0b6140f0179d 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -116,7 +116,7 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *
 			return res;
 	}
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	nexthop = rt6_nexthop((struct rt6_info *)dst, daddr);
 	neigh = __ipv6_neigh_lookup_noref(dev, nexthop);
 
@@ -124,7 +124,7 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *
 		if (unlikely(!neigh))
 			neigh = __neigh_create(&nd_tbl, nexthop, dev, false);
 		if (IS_ERR(neigh)) {
-			rcu_read_unlock_bh();
+			rcu_read_unlock();
 			IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTNOROUTES);
 			kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_CREATEFAIL);
 			return -EINVAL;
@@ -132,7 +132,7 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *
 	}
 	sock_confirm_neigh(skb, neigh);
 	ret = neigh_output(neigh, skb, false);
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 	return ret;
 }
 
@@ -1150,11 +1150,11 @@ static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
 	 * dst entry of the nexthop router
 	 */
 	rt = (struct rt6_info *) *dst;
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	n = __ipv6_neigh_lookup_noref(rt->dst.dev,
 				      rt6_nexthop(rt, &fl6->daddr));
 	err = n && !(READ_ONCE(n->nud_state) & NUD_VALID) ? -EINVAL : 0;
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	if (err) {
 		struct inet6_ifaddr *ifp;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index e829bd880384..244df77fac87 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -633,7 +633,7 @@ static void rt6_probe(struct fib6_nh *fib6_nh)
 
 	nh_gw = &fib6_nh->fib_nh_gw6;
 	dev = fib6_nh->fib_nh_dev;
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	last_probe = READ_ONCE(fib6_nh->last_probe);
 	idev = __in6_dev_get(dev);
 	neigh = __ipv6_neigh_lookup_noref(dev, nh_gw);
@@ -641,7 +641,7 @@ static void rt6_probe(struct fib6_nh *fib6_nh)
 		if (READ_ONCE(neigh->nud_state) & NUD_VALID)
 			goto out;
 
-		write_lock(&neigh->lock);
+		write_lock_bh(&neigh->lock);
 		if (!(neigh->nud_state & NUD_VALID) &&
 		    time_after(jiffies,
 			       neigh->updated + idev->cnf.rtr_probe_interval)) {
@@ -649,7 +649,7 @@ static void rt6_probe(struct fib6_nh *fib6_nh)
 			if (work)
 				__neigh_set_probe_once(neigh);
 		}
-		write_unlock(&neigh->lock);
+		write_unlock_bh(&neigh->lock);
 	} else if (time_after(jiffies, last_probe +
 				       idev->cnf.rtr_probe_interval)) {
 		work = kmalloc(sizeof(*work), GFP_ATOMIC);
@@ -667,7 +667,7 @@ static void rt6_probe(struct fib6_nh *fib6_nh)
 	}
 
 out:
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 }
 #else
 static inline void rt6_probe(struct fib6_nh *fib6_nh)
@@ -683,7 +683,7 @@ static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh)
 	enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 	struct neighbour *neigh;
 
-	rcu_read_lock_bh();
+	rcu_read_lock();
 	neigh = __ipv6_neigh_lookup_noref(fib6_nh->fib_nh_dev,
 					  &fib6_nh->fib_nh_gw6);
 	if (neigh) {
@@ -701,7 +701,7 @@ static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh)
 		ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 		      RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 	}
-	rcu_read_unlock_bh();
+	rcu_read_unlock();
 
 	return ret;
 }