From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Thu, 26 Oct 2017 18:24:36 -0700
Subject: net_sched: use tcf_queue_work() in u32 filter
Patch-mainline: v4.14-rc7
Git-commit: c0d378ef1266546a39f2df00a56ff1f74166a2b7
References: bsc#1109837
Defer the tcf_exts_destroy() in RCU callback to
tc filter workqueue and get RTNL lock.
Reported-by: Chris Mi <chrism@mellanox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
net/sched/cls_u32.c | 29 ++++++++++++++++++++++++++---
1 file changed, 26 insertions(+), 3 deletions(-)
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -68,7 +68,10 @@ struct tc_u_knode {
u32 __percpu *pcpu_success;
#endif
struct tcf_proto *tp;
- struct rcu_head rcu;
+ union {
+ struct work_struct work;
+ struct rcu_head rcu;
+ };
/* The 'sel' field MUST be the last field in structure to allow for
* tc_u32_keys allocated at end of structure.
*/
@@ -418,11 +421,21 @@ static int u32_destroy_key(struct tcf_pr
* this the u32_delete_key_rcu variant does not free the percpu
* statistics.
*/
+static void u32_delete_key_work(struct work_struct *work)
+{
+ struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
+
+ rtnl_lock();
+ u32_destroy_key(key->tp, key, false);
+ rtnl_unlock();
+}
+
static void u32_delete_key_rcu(struct rcu_head *rcu)
{
struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
- u32_destroy_key(key->tp, key, false);
+ INIT_WORK(&key->work, u32_delete_key_work);
+ tcf_queue_work(&key->work);
}
/* u32_delete_key_freepf_rcu is the rcu callback variant
@@ -432,11 +445,21 @@ static void u32_delete_key_rcu(struct rc
* for the variant that should be used with keys return from
* u32_init_knode()
*/
+static void u32_delete_key_freepf_work(struct work_struct *work)
+{
+ struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
+
+ rtnl_lock();
+ u32_destroy_key(key->tp, key, true);
+ rtnl_unlock();
+}
+
static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
{
struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
- u32_destroy_key(key->tp, key, true);
+ INIT_WORK(&key->work, u32_delete_key_freepf_work);
+ tcf_queue_work(&key->work);
}
static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)