Roland McGrath <roland@redhat.com> writes:

> Are you saying that if the ptracer dies, it can leave some threads in limbo?
> I think that case is supposed to work because forget_original_parent will
> move all the threads ptrace'd by the dying tracer process to be ptrace'd by
> init, which will then clean up their zombies as previously described.

Here is the test case, run it with "strace -f ./clone".  When the bug
happens then strace is stuck waiting for it's traced child that just died,
but you may have to try a few times before it happens.