Re: [PATCH] Fix for ptrace breakage

[Ingo Molnar]

> This patch fixes the following,
>
>    - race condition of ptrace flag
>    - sent odd signal to the tracer
>    - broken before behavior

(looks good to me). I'm wondering about the following:

-	while (!list_empty(&current->children))
-		zap_thread(list_entry(current->children.next,struct task_struct,sibling), current, 0);
-	while (!list_empty(&current->ptrace_children))
-		zap_thread(list_entry(current->ptrace_children.next,struct task_struct,ptrace_list), current, 1);
+	while ((p = eldest_child(current)) != NULL)
+		zap_thread(p, current);
 	BUG_ON(!list_empty(&current->children));

is it guaranteed that at this point current->ptrace_children is empty?

	Ingo