diff options
| author | Dominik Dingel <dingel@linux.vnet.ibm.com> | 2014-10-23 12:07:44 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2014-10-27 13:27:24 +0100 |
| commit | 593befa6ab74a805e4f503c8c737c3cffa8066b6 (patch) | |
| tree | cc8765c8ae5a8b26b0a618a93a6d13b4f73a1b56 /mm/memory.c | |
| parent | a13cff318cafbd493b8d5d679e5f3f761084c4fe (diff) | |
| download | lwn-593befa6ab74a805e4f503c8c737c3cffa8066b6.tar.gz lwn-593befa6ab74a805e4f503c8c737c3cffa8066b6.zip | |
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 <dingel@linux.vnet.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 2 |
1 files changed, 1 insertions, 1 deletions
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); |