pidns16: child should not get parent pid in parent NS

parent pid in parent NS is invisible to child, even when child got signalled
from parent, the signaller process should be fake parent (PID 0).

Signed-off-by: Monson Shao <jshao@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
1 file changed