On 01/29, Christian Brauner wrote: > > On Mon, Jan 29, 2024 at 12:23:15PM +0100, Oleg Nesterov wrote: > > @@ -3926,6 +3927,7 @@ SYSCALL_DEFINE4(pidfd_send_signal, int, pidfd, int, sig, > > prepare_kill_siginfo(sig, &kinfo); > > } > > > > + /* TODO: respect PIDFD_THREAD */ > > So I've been thinking about this at the end of last week. Do we need to > give userspace a way to send a thread-group wide signal even when a > PIDFD_THREAD pidfd is passed? Or should we just not worry about this > right now and wait until someone needs this? I don't know. I am fine either way, but I think this needs a separate patch and another discussion in any case. Anyway should be trivial, pidfd_send_signal() has the "flags" argument. On a related note, should copy_process(CLONE_PIDFD | CLONE_THREAD) add PIDFD_THREAD flag "automatically" depending on CLONE_THREAD? Or do we want another CLONE_PIDFD_THREAD flag so that PIDFD_THREAD can be used without CLONE_THREAD? Again, I do not know, needs another discussion. > Otherwise this looks good to me! OK, thanks, I'll send v2 in a minute. The patch is the same, I only updated the comments. Oleg.
