From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Thu, 26 Oct 2017 18:24:39 -0700
Subject: net_sched: use tcf_queue_work() in tcindex filter
Patch-mainline: v4.14-rc7
Git-commit: 27ce4f05e2abbe2d3ec7434e456619a5178cd3bd
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_tcindex.c | 38 +++++++++++++++++++++++++++++++++-----
1 file changed, 33 insertions(+), 5 deletions(-)
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -27,14 +27,20 @@
struct tcindex_filter_result {
struct tcf_exts exts;
struct tcf_result res;
- struct rcu_head rcu;
+ union {
+ struct work_struct work;
+ struct rcu_head rcu;
+ };
};
struct tcindex_filter {
u16 key;
struct tcindex_filter_result result;
struct tcindex_filter __rcu *next;
- struct rcu_head rcu;
+ union {
+ struct work_struct work;
+ struct rcu_head rcu;
+ };
};
@@ -133,12 +139,34 @@ static int tcindex_init(struct tcf_proto
return 0;
}
+static void tcindex_destroy_rexts_work(struct work_struct *work)
+{
+ struct tcindex_filter_result *r;
+
+ r = container_of(work, struct tcindex_filter_result, work);
+ rtnl_lock();
+ tcf_exts_destroy(&r->exts);
+ rtnl_unlock();
+}
+
static void tcindex_destroy_rexts(struct rcu_head *head)
{
struct tcindex_filter_result *r;
r = container_of(head, struct tcindex_filter_result, rcu);
- tcf_exts_destroy(&r->exts);
+ INIT_WORK(&r->work, tcindex_destroy_rexts_work);
+ tcf_queue_work(&r->work);
+}
+
+static void tcindex_destroy_fexts_work(struct work_struct *work)
+{
+ struct tcindex_filter *f = container_of(work, struct tcindex_filter,
+ work);
+
+ rtnl_lock();
+ tcf_exts_destroy(&f->result.exts);
+ kfree(f);
+ rtnl_unlock();
}
static void tcindex_destroy_fexts(struct rcu_head *head)
@@ -146,8 +174,8 @@ static void tcindex_destroy_fexts(struct
struct tcindex_filter *f = container_of(head, struct tcindex_filter,
rcu);
- tcf_exts_destroy(&f->result.exts);
- kfree(f);
+ INIT_WORK(&f->work, tcindex_destroy_fexts_work);
+ tcf_queue_work(&f->work);
}
static int tcindex_delete(struct tcf_proto *tp, void *arg, bool *last)