thp: pmd_trans_huge migrate bugcheck

[mv-sheeva.git] / mm / migrate.c

diff --git a/mm/migrate.c b/mm/migrate.c
index 690d0de993afb996997e5c4bca13a85d10ec0c0b..1a531b760b3bedb3b3395f95e4d1f2d1fbf8b4b5 100644 (file)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -113,6 +113,8 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma,
                        goto out;
 
                pmd = pmd_offset(pud, addr);
+               if (pmd_trans_huge(*pmd))
+                       goto out;
                if (!pmd_present(*pmd))
                        goto out;
 
@@ -632,6 +634,9 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
                /* page was freed from under us. So we are done. */
                goto move_newpage;
        }
+       if (unlikely(PageTransHuge(page)))
+               if (unlikely(split_huge_page(page)))
+                       goto move_newpage;
 
        /* prepare cgroup just returns 0 or -ENOMEM */
        rc = -EAGAIN;
@@ -1063,7 +1068,7 @@ static int do_move_page_to_node_array(struct mm_struct *mm,
                if (!vma || pp->addr < vma->vm_start || !vma_migratable(vma))
                        goto set_status;
 
-               page = follow_page(vma, pp->addr, FOLL_GET);
+               page = follow_page(vma, pp->addr, FOLL_GET|FOLL_SPLIT);
 
                err = PTR_ERR(page);
                if (IS_ERR(page))