diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index cdc63be63f2c..26d8df60a59f 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -4632,6 +4632,7 @@ int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts) void cgroup_file_notify(struct cgroup_file *cfile) { unsigned long flags; + struct kernfs_node *kn = NULL; spin_lock_irqsave(&cgroup_file_kn_lock, flags); if (cfile->kn) { @@ -4641,11 +4642,17 @@ void cgroup_file_notify(struct cgroup_file *cfile) if (time_in_range(jiffies, last, next)) { timer_reduce(&cfile->notify_timer, next); } else { - kernfs_notify(cfile->kn); + kn = cfile->kn; + kernfs_get(kn); cfile->notified_at = jiffies; } } spin_unlock_irqrestore(&cgroup_file_kn_lock, flags); + + if (kn) { + kernfs_notify(kn); + kernfs_put(kn); + } } EXPORT_SYMBOL_GPL(cgroup_file_notify);