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Date: Tue, 6 Feb 2024 10:04:08 -0700
From: Tycho Andersen <tycho@tycho.pizza>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>,
	Andy Lutomirski <luto@amacapital.net>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] pidfd: exit: kill the no longer used
 thread_group_exited()
Message-ID: <ZcJmiBxpaElivX2J@tycho.pizza>
References: <20240205174347.GA31461@redhat.com>
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On Mon, Feb 05, 2024 at 06:43:47PM +0100, Oleg Nesterov wrote:
> It was used by pidfd_poll() but now it has no callers.
> 
> If it finally finds a modular user we can revert this change, but note
> that the comment above this helper and the changelog in 38fd525a4c61
> ("exit: Factor thread_group_exited out of pidfd_poll") are not accurate,
> thread_group_exited() won't return true if all other threads have passed
> exit_notify() and are zombies, it returns true only when all other threads
> are completely gone. Not to mention that it can only work if the task
> identified by @pid is a thread-group leader.
> 
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>

Reviewed-by: Tycho Andersen <tandersen@netflix.com>