thp: pmd_trans_huge migrate bugcheck

No pmd_trans_huge should ever materialize in migration ptes areas, because
we split the hugepage before migration ptes are instantiated.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andrea Arcangeli
2011-01-13 15:46:55 -08:00
committed by Linus Torvalds
parent 0af4e98b6b
commit 500d65d471
3 changed files with 12 additions and 1 deletions

View File

@@ -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))