Commit 9aed8614 authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Linus Torvalds
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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: default avatarCyrill Gorcunov <gorcunov@openvz.org>
Acked-by: default avatarPavel Emelyanov <xemul@parallels.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent f0093ede
...@@ -2744,7 +2744,7 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address, ...@@ -2744,7 +2744,7 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address,
if (write) if (write)
entry = maybe_mkwrite(pte_mkdirty(entry), vma); entry = maybe_mkwrite(pte_mkdirty(entry), vma);
else if (pte_file(*pte) && pte_file_soft_dirty(*pte)) else if (pte_file(*pte) && pte_file_soft_dirty(*pte))
pte_mksoft_dirty(entry); entry = pte_mksoft_dirty(entry);
if (anon) { if (anon) {
inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES); inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES);
page_add_new_anon_rmap(page, vma, address); page_add_new_anon_rmap(page, vma, address);
......
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