> Is prepare_kill_siginfo() correct when we send a signal to the child > pid namespace? si_pid = task_tgid_vnr(current) doesn't look right in > this case but perhaps I am totally confused. > > And why do we need it at all? Can't sys_kill() and pidfd_send_signal() > just use SEND_SIG_NOINFO? Yeah, good point. I don't remember as it's been quite a while ago. My guess is that it just tried to mirror kill() itself without being aware of SEND_SIG_NOINFO. If you don't find anything wrong with this then switch it to SEND_SIG_NOINFO in a preparatory patch we can backport, please.
