[PATCHv5 06/19] mm/khugepaged: Handle encrypted pages
From: Kirill A. Shutemov <hidden>
Date: 2018-07-17 11:21:59
Also in:
lkml
Subsystem:
memory management, memory management - thp (transparent huge page), the rest · Maintainers:
Andrew Morton, David Hildenbrand, Lorenzo Stoakes, Linus Torvalds
khugepaged allocates page in advance, before we found a VMA for collapse. We don't yet know which KeyID to use for the allocation. The page is allocated with KeyID-0. Once we know that the VMA is suitable for collapsing, we prepare the page for KeyID we need, based on vma_keyid(). Signed-off-by: Kirill A. Shutemov <redacted> --- mm/khugepaged.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 5ae34097aed1..d116f4ebb622 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c@@ -1056,6 +1056,16 @@ static void collapse_huge_page(struct mm_struct *mm, */ anon_vma_unlock_write(vma->anon_vma); + /* + * At this point new_page is allocated as non-encrypted. + * If VMA's KeyID is non-zero, we need to prepare it to be encrypted + * before coping data. + */ + if (vma_keyid(vma)) { + prep_encrypted_page(new_page, HPAGE_PMD_ORDER, + vma_keyid(vma), false); + } + __collapse_huge_page_copy(pte, new_page, vma, address, pte_ptl); pte_unmap(pte); __SetPageUptodate(new_page);
--
2.18.0