dup_mmap of a VM_DONTCOPY vma forgot to lower the child's total_vm.  (But
no way does this account for the recent report of total_vm seen too low.)
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
                struct file *file;
 
                if (mpnt->vm_flags & VM_DONTCOPY) {
+                       long pages = vma_pages(mpnt);
+                       mm->total_vm -= pages;
                        __vm_stat_account(mm, mpnt->vm_flags, mpnt->vm_file,
-                                                       -vma_pages(mpnt));
+                                                               -pages);
                        continue;
                }
                charge = 0;