mm/autonuma: don't use set_pte_at when updating protnone ptes

	int last_cpupid;

	int target_nid;

	bool migrated = false;

	pte_t pte = vmf->orig_pte;

	bool was_writable = pte_write(pte);

	pte_t pte;

	bool was_writable = pte_write(vmf->orig_pte);

	int flags = 0;

	/*

	 * The "pte" at this point cannot be used safely without

	 * validation through pte_unmap_same(). It's of NUMA type but

	 * the pfn may be screwed if the read is non atomic.

	 *

	 * We can safely just do a "set_pte_at()", because the old

	 * page table entry is not accessible, so there would be no

	 * concurrent hardware modifications to the PTE.

	 */

	vmf->ptl = pte_lockptr(vma->vm_mm, vmf->pmd);

	spin_lock(vmf->ptl);

	if (unlikely(!pte_same(*vmf->pte, pte))) {

	if (unlikely(!pte_same(*vmf->pte, vmf->orig_pte))) {

		pte_unmap_unlock(vmf->pte, vmf->ptl);

		goto out;

	}

	/* Make it present again */

	/*

	 * Make it present again, Depending on how arch implementes non

	 * accessible ptes, some can allow access by kernel mode.

	 */

	pte = ptep_modify_prot_start(vma->vm_mm, vmf->address, vmf->pte);

	pte = pte_modify(pte, vma->vm_page_prot);

	pte = pte_mkyoung(pte);

	if (was_writable)

		pte = pte_mkwrite(pte);

	set_pte_at(vma->vm_mm, vmf->address, vmf->pte, pte);

	ptep_modify_prot_commit(vma->vm_mm, vmf->address, vmf->pte, pte);

	update_mmu_cache(vma, vmf->address, vmf->pte);

	page = vm_normal_page(vma, vmf->address, pte);