From 593befa6ab74a805e4f503c8c737c3cffa8066b6 Mon Sep 17 00:00:00 2001 From: Dominik Dingel Date: Thu, 23 Oct 2014 12:07:44 +0200 Subject: mm: introduce mm_forbids_zeropage function Add a new function stub to allow architectures to disable for an mm_structthe backing of non-present, anonymous pages with read-only empty zero pages. Signed-off-by: Dominik Dingel Reviewed-by: Paolo Bonzini Signed-off-by: Martin Schwidefsky --- mm/memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/memory.c') diff --git a/mm/memory.c b/mm/memory.c index 1cc6bfbd872e..d722d4f481c9 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2640,7 +2640,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, return VM_FAULT_SIGBUS; /* Use the zero-page for reads */ - if (!(flags & FAULT_FLAG_WRITE)) { + if (!(flags & FAULT_FLAG_WRITE) && !mm_forbids_zeropage(mm)) { entry = pte_mkspecial(pfn_pte(my_zero_pfn(address), vma->vm_page_prot)); page_table = pte_offset_map_lock(mm, pmd, address, &ptl); -- cgit v1.2.3-58-ga151