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Date: Fri, 9 Feb 2024 16:49:29 +0100
From: Christian Brauner <brauner@kernel.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>, 
	"Eric W. Biederman" <ebiederm@xmission.com>, Tycho Andersen <tycho@tycho.pizza>, linux-api@vger.kernel.org, 
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 2/2] pidfd: change pidfd_send_signal() to respect
 PIDFD_THREAD
Message-ID: <20240209-radeln-untrennbar-9d4ae05aa4cc@brauner>
References: <20240209130620.GA8039@redhat.com>
 <20240209130650.GA8048@redhat.com>
 <20240209-stangen-feuerzeug-17c8662854c9@brauner>
 <20240209154305.GC3282@redhat.com>
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In-Reply-To: <20240209154305.GC3282@redhat.com>

On Fri, Feb 09, 2024 at 04:43:05PM +0100, Oleg Nesterov wrote:
> On 02/09, Christian Brauner wrote:
> >
> > How do you feel about the following (untested...) addition?
> 
> LGTM, but let me read this patch once again tomorrow, I have
> a headache today.

Bah, feel better!

> 
> > I've played with PIDFD_SIGNAL_PROCESS_GROUP as well but that code is
> > fairly new to me so I would need some more time.
> 
> Heh, I was going to send another email to discuss this ;)
> 
> Should be simple, but may be need some simple preparations.
> 
> Especially if we also want PIDFD_SIGNAL_SESSION_GROUP.
> 
> So the question: do you think we also want PIDFD_SIGNAL_SESSION_GROUP?

Thought about this as well and my feeling is to wait until someone asks
for it. Right now, we have a reason to add PIDFD_SIGNAL_PROCESS_GROUP
because of Andy's use-case. If someone has a use-case for session groups
then yes. Otherwise I'd just not bother?