[PATCH 23 of 25] pmd_trans_huge migrate bugcheck

Andrea Arcangeli
2009-11-14T18:10:25Z

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

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
---

diff --git a/mm/migrate.c b/mm/migrate.c
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -102,6 +102,7 @@ static void remove_migration_pte(struct
return;

pmd = pmd_offset(pud, addr);
+ VM_BUG_ON(pmd_trans_huge(*pmd));
if (!pmd_present(*pmd))
return;