On 09/22, Michal Hocko wrote: > > --- a/kernel/signal.c > +++ b/kernel/signal.c > @@ -91,6 +91,10 @@ static int sig_ignored(struct task_struct *t, int sig, > bool force) > if (!sig_task_ignored(t, sig, force)) > return 0; > > + /* Do not ignore signals sent from child to the parent */ > + if (current->ptrace && current->parent == t) > + return 0;
This doesn't look right in general, and this can't really help. This assumes that the tracer will call do_wait() after mm_access() fails, but this is not necessarily true. Note also ptrace_attach(), -ERESTARTNOINTR means that the tracer won't even return to user-space if SIGCHLD is ignored, the tracer will silently restart the syscall. Oleg.