On Fri 23-09-16 12:21:41, Oleg Nesterov wrote: > 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.
Well, it apparently does help the strace case. So I am not arguing this is the best fix but can it be harmful? -- Michal Hocko SUSE Labs ------------------------------------------------------------------------------ _______________________________________________ Strace-devel mailing list Strace-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/strace-devel
