rk3368: support armoff

[firefly-linux-kernel-4.4.55.git] / mm / huge_memory.c

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index eb00e81601a54f2ae190e996d8bd34bbdc801b0d..d21c9ef0943c3b6173c3f71027e0f7ca6db92f0c 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1733,21 +1733,24 @@ static int __split_huge_page_map(struct page *page,
        if (pmd) {
                pgtable = pgtable_trans_huge_withdraw(mm);
                pmd_populate(mm, &_pmd, pgtable);
+               if (pmd_write(*pmd))
+                       BUG_ON(page_mapcount(page) != 1);
 
                haddr = address;
                for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) {
                        pte_t *pte, entry;
                        BUG_ON(PageCompound(page+i));
+                       /*
+                        * Note that pmd_numa is not transferred deliberately
+                        * to avoid any possibility that pte_numa leaks to
+                        * a PROT_NONE VMA by accident.
+                        */
                        entry = mk_pte(page + i, vma->vm_page_prot);
                        entry = maybe_mkwrite(pte_mkdirty(entry), vma);
                        if (!pmd_write(*pmd))
                                entry = pte_wrprotect(entry);
-                       else
-                               BUG_ON(page_mapcount(page) != 1);
                        if (!pmd_young(*pmd))
                                entry = pte_mkold(entry);
-                       if (pmd_numa(*pmd))
-                               entry = pte_mknuma(entry);
                        pte = pte_offset_map(&_pmd, haddr);
                        BUG_ON(!pte_none(*pte));
                        set_pte_at(mm, haddr, pte, entry);