__trace_remove_event_dirs() leaks file->filter ? (Was: probe_event_disable()->synchronize_sched())

[Oleg Nesterov <oleg@redhat.com>]

On 07/03, Oleg Nesterov wrote:
>
> Hmm. Off-topic, but it seems that instance_rmdir() leaks the memory? Say,
> file->filter?

Perhaps I am totally confused, but don't we need something like the patch
below? I'll try to recheck later...

Better yet, we can probably move destroy_preds() from event_remove() to
remove_event_file_dir()... not sure, need to recheck.

Oleg.

--- x/kernel/trace/trace_events.c
+++ x/kernel/trace/trace_events.c
@@ -470,6 +470,7 @@ static void remove_event_file_dir(struct ftrace_event_file *file)
 
 	list_del(&file->list);
 	remove_subsystem(file->system);
+	destroy_file_preds(file);
 	kmem_cache_free(file_cachep, file);
 }