1 files changed, 5 insertions, 8 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 0272305bf855..464971e6923e 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -557,7 +557,7 @@ static void reparent_leader(struct task_struct *father, struct task_struct *p,
 
 static void forget_original_parent(struct task_struct *father)
 {
-        struct task_struct *p, *n, *reaper;
+        struct task_struct *p, *t, *n, *reaper;
         LIST_HEAD(dead_children);
 
         write_lock_irq(&tasklist_lock);
@@ -569,18 +569,15 @@ static void forget_original_parent(struct task_struct *father)
         reaper = find_new_reaper(father);
 
         list_for_each_entry_safe(p, n, &father->children, sibling) {
-                struct task_struct *t = p;
-
-                do {
+                for_each_thread(p, t) {
                         t->real_parent = reaper;
-                        if (t->parent == father) {
-                                BUG_ON(t->ptrace);
+                        BUG_ON((!t->ptrace) != (t->parent == father));
+                        if (likely(!t->ptrace))
                                 t->parent = t->real_parent;
-                        }
                         if (t->pdeath_signal)
                                 group_send_sig_info(t->pdeath_signal,
                                                     SEND_SIG_NOINFO, t);
-                } while_each_thread(p, t);
+                }
                 reparent_leader(father, p, &dead_children);
         }
         write_unlock_irq(&tasklist_lock);