mm/hugetlb.c: add missing spin_lock() to hugetlb_cow()

Add missing spin_lock() of the page_table_lock before an error return in hugetlb_cow(). Callers of hugtelb_cow() expect it to be held upon return. Signed-off-by: Dean Nelson <[email protected]> Cc: Mel Gorman <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
sudhin-joseph · Oct 26, 2010 · 44e2aa9 · 44e2aa9
1 parent 70384dc
commit 44e2aa9
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
@@ -2448,8 +2448,11 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
 	 * When the original hugepage is shared one, it does not have
 	 * anon_vma prepared.
 	 */
-	if (unlikely(anon_vma_prepare(vma)))
+	if (unlikely(anon_vma_prepare(vma))) {
+		/* Caller expects lock to be held */
+		spin_lock(&mm->page_table_lock);
 		return VM_FAULT_OOM;
+	}
 
 	copy_user_huge_page(new_page, old_page, address, vma);
 	__SetPageUptodate(new_page);