diff options
| author | Cyrill Gorcunov <gorcunov@gmail.com> | 2014-07-17 10:58:01 +1000 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2014-07-17 10:58:01 +1000 |
| commit | 765deb1739adb542b12137adb75e50532f088909 (patch) | |
| tree | e8e0e531c831674ae8747c372e0ee0710b410c1c /mm | |
| parent | 41be98a15413a36fe124575bb40e29b863e62f54 (diff) | |
mm/memory.c: don't forget to set softdirty on file mapped fault
Otherwise we may not notice that pte was softdirty because
pte_mksoft_dirty helper _returns_ new pte but doesn't modify the argument.
In case if page fault happend on dirty filemapping the newly created pte
may loose softdirty bit thus if a userspace program is tracking memory
changes with help of a memory tracker (CONFIG_MEM_SOFT_DIRTY) it might
miss modification of a memory page (which in worts case may lead to
data inconsistency).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
| -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 9c0cf0c09ceb..ab87cf4859f9 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2746,7 +2746,7 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address, if (write) entry = maybe_mkwrite(pte_mkdirty(entry), vma); else if (pte_file(*pte) && pte_file_soft_dirty(*pte)) - pte_mksoft_dirty(entry); + entry = pte_mksoft_dirty(entry); if (anon) { inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES); page_add_new_anon_rmap(page, vma, address); |