static phys_addr_t pgd_pgtable_alloc(void)
{
	void *ptr = (void *)__get_free_page(PGALLOC_GFP);
	if (!ptr || !pgtable_page_ctor(virt_to_page(ptr)))
		BUG();

	/* Ensure the zeroed page is visible to the page table walker */
	dsb(ishst);
	return __pa(ptr);
}
static phys_addr_t pgd_pgtable_alloc(void)
{
	void *ptr = (void *)__get_free_page(PGALLOC_GFP);
	if (!ptr || !pgtable_page_ctor(virt_to_page(ptr)))
		BUG();

	 
	dsb(ishst);
	return __pa(ptr);
}