1 files changed, 59 insertions, 12 deletions

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index f62de5f43e79..f2896d13001b 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -116,6 +116,7 @@ struct hist_field {
 	struct ftrace_event_field	*field;
 	unsigned long			flags;
 	hist_field_fn_t			fn;
+	unsigned int			ref;
 	unsigned int			size;
 	unsigned int			offset;
 	unsigned int                    is_signed;
@@ -1154,6 +1155,12 @@ static struct synth_event *find_synth_event(const char *name)
 	return NULL;
 }
 
+static struct trace_event_fields synth_event_fields_array[] = {
+	{ .type = TRACE_FUNCTION_TYPE,
+	  .define_fields = synth_event_define_fields },
+	{}
+};
+
 static int register_synth_event(struct synth_event *event)
 {
 	struct trace_event_call *call = &event->call;
@@ -1175,7 +1182,7 @@ static int register_synth_event(struct synth_event *event)
 
 	INIT_LIST_HEAD(&call->class->fields);
 	call->event.funcs = &synth_event_funcs;
-	call->class->define_fields = synth_event_define_fields;
+	call->class->fields_array = synth_event_fields_array;
 
 	ret = register_trace_event(&call->event);
 	if (!ret) {
@@ -1766,11 +1773,13 @@ static struct hist_field *find_var(struct hist_trigger_data *hist_data,
 	struct event_trigger_data *test;
 	struct hist_field *hist_field;
 
+	lockdep_assert_held(&event_mutex);
+
 	hist_field = find_var_field(hist_data, var_name);
 	if (hist_field)
 		return hist_field;
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			test_data = test->private_data;
 			hist_field = find_var_field(test_data, var_name);
@@ -1820,7 +1829,9 @@ static struct hist_field *find_file_var(struct trace_event_file *file,
 	struct event_trigger_data *test;
 	struct hist_field *hist_field;
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	lockdep_assert_held(&event_mutex);
+
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			test_data = test->private_data;
 			hist_field = find_var_field(test_data, var_name);
@@ -2423,8 +2434,16 @@ static int contains_operator(char *str)
 	return field_op;
 }
 
+static void get_hist_field(struct hist_field *hist_field)
+{
+	hist_field->ref++;
+}
+
 static void __destroy_hist_field(struct hist_field *hist_field)
 {
+	if (--hist_field->ref > 1)
+		return;
+
 	kfree(hist_field->var.name);
 	kfree(hist_field->name);
 	kfree(hist_field->type);
@@ -2466,6 +2485,8 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	if (!hist_field)
 		return NULL;
 
+	hist_field->ref = 1;
+
 	hist_field->hist_data = hist_data;
 
 	if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
@@ -2661,6 +2682,17 @@ static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data,
 {
 	unsigned long flags = HIST_FIELD_FL_VAR_REF;
 	struct hist_field *ref_field;
+	int i;
+
+	/* Check if the variable already exists */
+	for (i = 0; i < hist_data->n_var_refs; i++) {
+		ref_field = hist_data->var_refs[i];
+		if (ref_field->var.idx == var_field->var.idx &&
+		    ref_field->var.hist_data == var_field->hist_data) {
+			get_hist_field(ref_field);
+			return ref_field;
+		}
+	}
 
 	ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
 	if (ref_field) {
@@ -3115,7 +3147,9 @@ static char *find_trigger_filter(struct hist_trigger_data *hist_data,
 {
 	struct event_trigger_data *test;
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	lockdep_assert_held(&event_mutex);
+
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			if (test->private_data == hist_data)
 				return test->filter_str;
@@ -3166,9 +3200,11 @@ find_compatible_hist(struct hist_trigger_data *target_hist_data,
 	struct event_trigger_data *test;
 	unsigned int n_keys;
 
+	lockdep_assert_held(&event_mutex);
+
 	n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			hist_data = test->private_data;
 
@@ -5528,7 +5564,7 @@ static int hist_show(struct seq_file *m, void *v)
 		goto out_unlock;
 	}
 
-	list_for_each_entry_rcu(data, &event_file->triggers, list) {
+	list_for_each_entry(data, &event_file->triggers, list) {
 		if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
 			hist_trigger_show(m, data, n++);
 	}
@@ -5921,7 +5957,9 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
 	if (hist_data->attrs->name && !named_data)
 		goto new;
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	lockdep_assert_held(&event_mutex);
+
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			if (!hist_trigger_match(data, test, named_data, false))
 				continue;
@@ -6005,10 +6043,12 @@ static bool have_hist_trigger_match(struct event_trigger_data *data,
 	struct event_trigger_data *test, *named_data = NULL;
 	bool match = false;
 
+	lockdep_assert_held(&event_mutex);
+
 	if (hist_data->attrs->name)
 		named_data = find_named_trigger(hist_data->attrs->name);
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			if (hist_trigger_match(data, test, named_data, false)) {
 				match = true;
@@ -6026,10 +6066,12 @@ static bool hist_trigger_check_refs(struct event_trigger_data *data,
 	struct hist_trigger_data *hist_data = data->private_data;
 	struct event_trigger_data *test, *named_data = NULL;
 
+	lockdep_assert_held(&event_mutex);
+
 	if (hist_data->attrs->name)
 		named_data = find_named_trigger(hist_data->attrs->name);
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			if (!hist_trigger_match(data, test, named_data, false))
 				continue;
@@ -6051,10 +6093,12 @@ static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
 	struct event_trigger_data *test, *named_data = NULL;
 	bool unregistered = false;
 
+	lockdep_assert_held(&event_mutex);
+
 	if (hist_data->attrs->name)
 		named_data = find_named_trigger(hist_data->attrs->name);
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			if (!hist_trigger_match(data, test, named_data, false))
 				continue;
@@ -6080,7 +6124,9 @@ static bool hist_file_check_refs(struct trace_event_file *file)
 	struct hist_trigger_data *hist_data;
 	struct event_trigger_data *test;
 
-	list_for_each_entry_rcu(test, &file->triggers, list) {
+	lockdep_assert_held(&event_mutex);
+
+	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			hist_data = test->private_data;
 			if (check_var_refs(hist_data))
@@ -6323,7 +6369,8 @@ hist_enable_trigger(struct event_trigger_data *data, void *rec,
 	struct enable_trigger_data *enable_data = data->private_data;
 	struct event_trigger_data *test;
 
-	list_for_each_entry_rcu(test, &enable_data->file->triggers, list) {
+	list_for_each_entry_rcu(test, &enable_data->file->triggers, list,
+				lockdep_is_held(&event_mutex)) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
 			if (enable_data->enable)
 				test->paused = false;