diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-07-26 15:25:53 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-26 16:19:19 -0700 |
| commit | 9a73f61bdb8acdc01bbaf72a3fe0a8854f2463ad (patch) | |
| tree | add475877423bc5ae648e67d221324ceaa388fcf /mm/mmap.c | |
| parent | baa355fd331424526e742d41d9b90d5f9d10f716 (diff) | |
| download | lwn-9a73f61bdb8acdc01bbaf72a3fe0a8854f2463ad.tar.gz lwn-9a73f61bdb8acdc01bbaf72a3fe0a8854f2463ad.zip | |
thp, mlock: do not mlock PTE-mapped file huge pages
As with anon THP, we only mlock file huge pages if we can prove that the
page is not mapped with PTE. This way we can avoid mlock leak into
non-mlocked vma on split.
We rely on PageDoubleMap() under lock_page() to check if the the page
may be PTE mapped. PG_double_map is set by page_add_file_rmap() when
the page mapped with PTEs.
Link: http://lkml.kernel.org/r/1466021202-61880-21-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/mmap.c')
| -rw-r--r-- | mm/mmap.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 31f9b2220b72..a41872c8f2af 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2591,6 +2591,12 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, /* drop PG_Mlocked flag for over-mapped range */ for (tmp = vma; tmp->vm_start >= start + size; tmp = tmp->vm_next) { + /* + * Split pmd and munlock page on the border + * of the range. + */ + vma_adjust_trans_huge(tmp, start, start + size, 0); + munlock_vma_pages_range(tmp, max(tmp->vm_start, start), min(tmp->vm_end, start + size)); |