From 6041421dd0876356794d49db00b65bb831066ad6 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Thu, 2 Jul 2026 04:44:14 +0000 Subject: [PATCH 1/2] ipv4: fib: Define fib_table_hash_lock under CONFIG_IP_MULTIPLE_TABLES. When CONFIG_IP_MULTIPLE_TABLES is disabled, fib_new_table() is fib_get_table(), and no new table is created. Let's move net->ipv4.fib_table_hash_lock under CONFIG_IP_MULTIPLE_TABLES. While at it, netns_ipv4_sysctl.rst is updated. Suggested-by: Ido Schimmel Signed-off-by: Kuniyuki Iwashima Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/20260702044437.591864-2-kuniyu@google.com Signed-off-by: Paolo Abeni --- Documentation/networking/net_cachelines/netns_ipv4_sysctl.rst | 1 + include/net/netns/ipv4.h | 2 +- net/ipv4/fib_frontend.c | 3 +++ 3 files changed, 5 insertions(+), 1 deletion(-) diff --git a/Documentation/networking/net_cachelines/netns_ipv4_sysctl.rst b/Documentation/networking/net_cachelines/netns_ipv4_sysctl.rst index 6dbd97d435e9..3dc03bff739e 100644 --- a/Documentation/networking/net_cachelines/netns_ipv4_sysctl.rst +++ b/Documentation/networking/net_cachelines/netns_ipv4_sysctl.rst @@ -22,6 +22,7 @@ struct_mutex ra_mutex struct_fib_rules_ops* rules_ops struct_fib_table fib_main struct_fib_table fib_default +spinlock_t fib_table_hash_lock unsigned_int fib_rules_require_fldissect bool fib_has_custom_rules bool fib_has_custom_local_routes diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index 59506320558a..cb7f8bf15671 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -118,6 +118,7 @@ struct netns_ipv4 { struct fib_rules_ops *rules_ops; struct fib_table __rcu *fib_main; struct fib_table __rcu *fib_default; + spinlock_t fib_table_hash_lock; unsigned int fib_rules_require_fldissect; bool fib_has_custom_rules; #endif @@ -127,7 +128,6 @@ struct netns_ipv4 { atomic_t fib_num_tclassid_users; #endif struct hlist_head *fib_table_hash; - spinlock_t fib_table_hash_lock; struct sock *fibnl; struct hlist_head *fib_info_hash; unsigned int fib_info_hash_bits; diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index a5e739d32d59..8a3dc04e8cac 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1584,7 +1584,10 @@ static int __net_init ip_fib_net_init(struct net *net) net->ipv4.sysctl_fib_multipath_hash_fields = FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK; #endif + +#ifdef CONFIG_IP_MULTIPLE_TABLES spin_lock_init(&net->ipv4.fib_table_hash_lock); +#endif /* Avoid false sharing : Use at least a full cache line */ size = max_t(size_t, size, L1_CACHE_BYTES); From 99c13f8020df1b06f68044ec93649b0b50f37d79 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Thu, 2 Jul 2026 04:44:15 +0000 Subject: [PATCH 2/2] net: fib_rules: Destroy ops->lock in fib_rules_unregister(). Commit 8e133ba99cd8 ("net: fib_rules: Add fib_rules_ops.lock.") added mutex in struct fib_rules_ops, which is initialised in fib_rules_register(). Let's add paired mutex_destroy() in fib_rules_unregister(). Signed-off-by: Kuniyuki Iwashima Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/20260702044437.591864-3-kuniyu@google.com Signed-off-by: Paolo Abeni --- net/core/fib_rules.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index 22e5e5e1a9c4..7df216c17c67 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -203,6 +203,7 @@ void fib_rules_unregister(struct fib_rules_ops *ops) spin_unlock(&net->rules_mod_lock); fib_rules_cleanup_ops(ops); + mutex_destroy(&ops->lock); kfree_rcu(ops, rcu); }