mm: softdirty: don't forget to save file map softdiry bit on unmap
pte_file_mksoft_dirty operates with argument passed by a value and
returns modified result thus we need to assign @ptfile here, otherwise
itis a no-op which may lead to loss of the softdirty bit.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/rmap.c b/mm/rmap.c
index 10aef96..7da400d 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1361,7 +1361,7 @@
if (page->index != linear_page_index(vma, address)) {
pte_t ptfile = pgoff_to_pte(page->index);
if (pte_soft_dirty(pteval))
- pte_file_mksoft_dirty(ptfile);
+ ptfile = pte_file_mksoft_dirty(ptfile);
set_pte_at(mm, address, pte, ptfile);
}