I've follow the kb but when execute strace i've this output:
Process 9130 attached
restart_syscall(<... resuming interrupted call ...>) = 0
poll([{fd=7, events=POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND}], 1, 1000) = 0 (Timeout)
poll([{fd=7, events=POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND}], 1, 1000) = 0...