[PATCH v3 net-next 09/15] ip6mr: Call fib_rules_unregister() without RTNL.

[Kuniyuki Iwashima <kuniyu@google.com>]

fib_rules_unregister() removes ops from net->rules_ops under
spinlock, calls ops->delete() for each rule, and frees the ops.

ip6mr_rules_ops_template does not have ->delete(), and any
operation does not require RTNL there.

Let's move fib_rules_unregister() from ip6mr_rules_exit() to
ip6mr_net_exit().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
---
 net/ipv6/ip6mr.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index ddbe06397d9c..bb613331ead2 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -259,6 +259,11 @@ static int __net_init ip6mr_rules_init(struct net *net)
 }
 
 static void __net_exit ip6mr_rules_exit(struct net *net)
+{
+	fib_rules_unregister(net->ipv6.mr6_rules_ops);
+}
+
+static void __net_exit ip6mr_rules_exit_rtnl(struct net *net)
 {
 	struct mr_table *mrt, *next;
 
@@ -267,7 +272,6 @@ static void __net_exit ip6mr_rules_exit(struct net *net)
 		list_del_rcu(&mrt->list);
 		ip6mr_free_table(mrt);
 	}
-	fib_rules_unregister(net->ipv6.mr6_rules_ops);
 }
 
 static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
@@ -328,6 +332,10 @@ static int __net_init ip6mr_rules_init(struct net *net)
 }
 
 static void __net_exit ip6mr_rules_exit(struct net *net)
+{
+}
+
+static void __net_exit ip6mr_rules_exit_rtnl(struct net *net)
 {
 	struct mr_table *mrt = rcu_dereference_protected(net->ipv6.mrt6, 1);
 
@@ -1366,8 +1374,9 @@ static int __net_init ip6mr_net_init(struct net *net)
 	remove_proc_entry("ip6_mr_vif", net->proc_net);
 proc_vif_fail:
 	rtnl_lock();
-	ip6mr_rules_exit(net);
+	ip6mr_rules_exit_rtnl(net);
 	rtnl_unlock();
+	ip6mr_rules_exit(net);
 #endif
 ip6mr_rules_fail:
 	ip6mr_notifier_exit(net);
@@ -1380,6 +1389,7 @@ static void __net_exit ip6mr_net_exit(struct net *net)
 	remove_proc_entry("ip6_mr_cache", net->proc_net);
 	remove_proc_entry("ip6_mr_vif", net->proc_net);
 #endif
+	ip6mr_rules_exit(net);
 	ip6mr_notifier_exit(net);
 }
 
@@ -1389,7 +1399,7 @@ static void __net_exit ip6mr_net_exit_batch(struct list_head *net_list)
 
 	rtnl_lock();
 	list_for_each_entry(net, net_list, exit_list)
-		ip6mr_rules_exit(net);
+		ip6mr_rules_exit_rtnl(net);
 	rtnl_unlock();
 }
 
-- 
2.54.0.1032.g2f8565e1d1-goog