ksm: fix oom deadlock

[safe/jmp/linux-2.6] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index 1a435b8..f47ffe9 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2648,8 +2648,9 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
        entry = maybe_mkwrite(pte_mkdirty(entry), vma);
 
        page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
-       if (!pte_none(*page_table))
+       if (!pte_none(*page_table) || ksm_test_exit(mm))
                goto release;
+
        inc_mm_counter(mm, anon_rss);
        page_add_new_anon_rmap(page, vma, address);
        set_pte_at(mm, address, page_table, entry);
@@ -2791,7 +2792,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
         * handle that later.
         */
        /* Only go through if we didn't race with anybody else... */
-       if (likely(pte_same(*page_table, orig_pte))) {
+       if (likely(pte_same(*page_table, orig_pte) && !ksm_test_exit(mm))) {
                flush_icache_page(vma, page);
                entry = mk_pte(page, vma->vm_page_prot);
                if (flags & FAULT_FLAG_WRITE)