mm: let mm_find_pmd fix buggy race with THP fault

[linux-beck.git] / mm / ksm.c

diff --git a/mm/ksm.c b/mm/ksm.c
index aa4c7c7250c11a95b9676b70c7cc38f987d88717..346ddc9e4c0da44ed0c24b63d49cd40bc3d813de 100644 (file)
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -444,7 +444,7 @@ static void break_cow(struct rmap_item *rmap_item)
 static struct page *page_trans_compound_anon(struct page *page)
 {
        if (PageTransCompound(page)) {
-               struct page *head = compound_trans_head(page);
+               struct page *head = compound_head(page);
                /*
                 * head may actually be splitted and freed from under
                 * us but it's ok here.
@@ -945,7 +945,6 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
        pmd = mm_find_pmd(mm, addr);
        if (!pmd)
                goto out;
-       BUG_ON(pmd_trans_huge(*pmd));
 
        mmun_start = addr;
        mmun_end   = addr + PAGE_SIZE;