If __unmap_hugepage_range() tries to unmap the address range over which
hugepage migration is on the way, we get the wrong page because pte_page()
doesn't work for migration entries. This patch calls pte_to_swp_entry() and
migration_entry_to_page() to get the right page for migration entries.
Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # [2.6.36+]
---
mm/hugetlb.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git mmotm-2014-08-25-16-52.orig/mm/hugetlb.c mmotm-2014-08-25-16-52/mm/hugetlb.c
index 1ed9df6def54..0a4511115ee0 100644
--- mmotm-2014-08-25-16-52.orig/mm/hugetlb.c
+++ mmotm-2014-08-25-16-52/mm/hugetlb.c
@@ -2652,6 +2652,13 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
if (huge_pte_none(pte))
goto unlock;
+ if (unlikely(is_hugetlb_entry_migration(pte))) {
+ swp_entry_t entry = pte_to_swp_entry(pte);
+
+ page = migration_entry_to_page(entry);
+ goto clear;
+ }
+
/*
* HWPoisoned hugepage is already unmapped and dropped reference
*/
@@ -2677,7 +2684,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
*/
set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED);
}
-
+clear:
pte = huge_ptep_get_and_clear(mm, address, ptep);
tlb_remove_tlb_entry(tlb, ptep, address);
if (huge_pte_dirty(pte))
--
1.9.3
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>