[PATCH 1/2] ftrace: clear module from hash of all ftrace ops

[Chengming Zhou <zhouchengming@bytedance.com>]

We should clear module from hash of all ops on ftrace_ops_list when
module going, or the ops including these modules will be matched
wrongly by new module loaded later.

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
 kernel/trace/ftrace.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 1903b80db6eb..fca01a168ae5 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -6223,18 +6223,20 @@ clear_mod_from_hash(struct ftrace_page *pg, struct ftrace_hash *hash)
 /* Clear any records from hashs */
 static void clear_mod_from_hashes(struct ftrace_page *pg)
 {
-	struct trace_array *tr;
+	struct ftrace_ops *op;
 
-	mutex_lock(&trace_types_lock);
-	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
-		if (!tr->ops || !tr->ops->func_hash)
+	mutex_lock(&ftrace_lock);
+
+	do_for_each_ftrace_op(op, ftrace_ops_list) {
+		if (!op->func_hash)
 			continue;
-		mutex_lock(&tr->ops->func_hash->regex_lock);
-		clear_mod_from_hash(pg, tr->ops->func_hash->filter_hash);
-		clear_mod_from_hash(pg, tr->ops->func_hash->notrace_hash);
-		mutex_unlock(&tr->ops->func_hash->regex_lock);
-	}
-	mutex_unlock(&trace_types_lock);
+		mutex_lock(&op->func_hash->regex_lock);
+		clear_mod_from_hash(pg, op->func_hash->filter_hash);
+		clear_mod_from_hash(pg, op->func_hash->notrace_hash);
+		mutex_unlock(&op->func_hash->regex_lock);
+	} while_for_each_ftrace_op(op);
+
+	mutex_unlock(&ftrace_lock);
 }
 
 static void ftrace_free_mod_map(struct rcu_head *rcu)
-- 
2.20.1