mm: thp: fix BUG on mm->nr_ptes

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

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 78a83e7169968fa254dba439b8920e86f00eafe7..8cc11dda6a747e4e9e823c8f988fd441a4b43ad9 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -641,6 +641,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
                set_pmd_at(mm, haddr, pmd, entry);
                prepare_pmd_huge_pte(pgtable, mm);
                add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
+               mm->nr_ptes++;
                spin_unlock(&mm->page_table_lock);
        }
 
@@ -759,6 +760,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
        pmd = pmd_mkold(pmd_wrprotect(pmd));
        set_pmd_at(dst_mm, addr, dst_pmd, pmd);
        prepare_pmd_huge_pte(pgtable, dst_mm);
+       dst_mm->nr_ptes++;
 
        ret = 0;
 out_unlock:
@@ -857,7 +859,6 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
        }
        kfree(pages);
 
-       mm->nr_ptes++;
        smp_wmb(); /* make pte visible before pmd */
        pmd_populate(mm, pmd, pgtable);
        page_remove_rmap(page);
@@ -1016,6 +1017,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
                        VM_BUG_ON(page_mapcount(page) < 0);
                        add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
                        VM_BUG_ON(!PageHead(page));
+                       tlb->mm->nr_ptes--;
                        spin_unlock(&tlb->mm->page_table_lock);
                        tlb_remove_page(tlb, page);
                        pte_free(tlb->mm, pgtable);
@@ -1310,7 +1312,6 @@ static int __split_huge_page_map(struct page *page,
                        pte_unmap(pte);
                }
 
-               mm->nr_ptes++;
                smp_wmb(); /* make pte visible before pmd */
                /*
                 * Up to this point the pmd is present and huge and
@@ -1925,7 +1926,6 @@ static void collapse_huge_page(struct mm_struct *mm,
        set_pmd_at(mm, address, pmd, _pmd);
        update_mmu_cache(vma, address, entry);
        prepare_pmd_huge_pte(pgtable, mm);
-       mm->nr_ptes--;
        spin_unlock(&mm->page_table_lock);
 
 #ifndef CONFIG_NUMA