[PATCH v1 net-next 10/15] ipmr: Remove RTNL in ipmr_rules_init() and ipmr_net_init().
From: Kuniyuki Iwashima <kuniyu@google.com>
Date: 2026-02-26 02:36:56
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
When ipmr_free_table() is called from ipmr_rules_init() or ipmr_net_init(), the netns is not yet published. Thus, no device should have been registered, and mroute_clean_tables() will not call vif_delete(), so unregister_netdevice_many() is unnecessary. unregister_netdevice_many() does nothing if the list is empty, but it requires RTNL due to the unconditional ASSERT_RTNL() at the entry of unregister_netdevice_many_notify(). Let's remove unnecessary RTNL and ASSERT_RTNL() and instead add WARN_ON_ONCE() in ipmr_free_table(). Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> --- net/ipv4/ipmr.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 3526c9afcb03..537be40af9e0 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c@@ -276,10 +276,7 @@ static int __net_init ipmr_rules_init(struct net *net) return 0; err2: - rtnl_lock(); ipmr_free_table(mrt, &dev_kill_list); - unregister_netdevice_many(&dev_kill_list); - rtnl_unlock(); err1: fib_rules_unregister(ops); return err;
@@ -290,7 +287,6 @@ static void __net_exit ipmr_rules_exit_rtnl(struct net *net, { struct mr_table *mrt, *next; - ASSERT_RTNL(); list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) { list_del(&mrt->list); ipmr_free_table(mrt, dev_kill_list);
@@ -355,8 +351,6 @@ static int __net_init ipmr_rules_init(struct net *net) static void __net_exit ipmr_rules_exit_rtnl(struct net *net, struct list_head *dev_kill_list) { - ASSERT_RTNL(); - ipmr_free_table(net->ipv4.mrt, dev_kill_list); net->ipv4.mrt = NULL;
@@ -445,6 +439,8 @@ static void ipmr_free_table(struct mr_table *mrt, struct list_head *dev_kill_lis dev_kill_list); rhltable_destroy(&mrt->mfc_hash); kfree(mrt); + + WARN_ON_ONCE(!net_initialized(net) && !list_empty(dev_kill_list)); } /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
@@ -3287,10 +3283,7 @@ static int __net_init ipmr_net_init(struct net *net) proc_cache_fail: remove_proc_entry("ip_mr_vif", net->proc_net); proc_vif_fail: - rtnl_lock(); ipmr_rules_exit_rtnl(net, &dev_kill_list); - unregister_netdevice_many(&dev_kill_list); - rtnl_unlock(); #endif ipmr_rules_fail: ipmr_notifier_exit(net);
--
2.53.0.414.gf7e9f6c205-goog