__mmu_notifier_register
ret = __mmu_notifier_register(&encl_mm->mmu_notifier, mm);
ret = __mmu_notifier_register(&svmm->notifier, current->mm);
extern int __mmu_notifier_register(struct mmu_notifier *subscription,
ret = __mmu_notifier_register(NULL, mm);
EXPORT_SYMBOL_GPL(__mmu_notifier_register);
ret = __mmu_notifier_register(subscription, mm);
ret = __mmu_notifier_register(subscription, mm);