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Date:   Fri, 30 Jul 2021 01:41:07 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christian Brauner <christian.brauner@ubuntu.com>
Cc:     John Cotton Ericson <mail@johnericson.me>,
        LKML <linux-kernel@vger.kernel.org>,
        David Laight <David.Laight@aculab.com>,
        Andy Lutomirski <luto@kernel.org>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        Jann Horn <jann@thejh.net>,
        Christian Brauner <christian.brauner@canonical.com>
Subject: Re: Leveraging pidfs for process creation without fork
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On Thu, Jul 29, 2021 at 04:24:15PM +0200, Christian Brauner wrote:
> On Wed, Jul 28, 2021 at 12:37:57PM -0400, John Cotton Ericson wrote:
> > Hi,
> > 
> > I was excited to learn about about pidfds the other day, precisely in hopes
> > that it would open the door to such a "sane process creation API". I
> > searched the LKML, found this thread, and now hope to rekindle the
> > discussion; my apologies if there has been more discussion since that I
> 
> Yeah, I haven't forgotten this discussion. A proposal is on my todo list
> for this year. So far I've scheduled some time to work on this in the
> fall.

Keep in mind that quite a few places in kernel/exit.c very much rely upon the
lack of anything outside of thread group adding threads into it.  Same for
fs/exec.c.