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From: Oleg Nesterov <oleg@redhat.com>
To: Jim Newsome <jnewsome@torproject.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Christian Brauner <christian@brauner.io>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] do_wait: make PIDTYPE_PID case O(1) instead of O(n)
Date: Thu, 11 Mar 2021 16:15:43 +0100	[thread overview]
Message-ID: <20210311151542.GB15552@redhat.com> (raw)
In-Reply-To: <4d9006b4-b65a-6ce0-b367-971f29de1f21@torproject.org>

On 03/10, Jim Newsome wrote:
>
> On 3/10/21 16:40, Eric W. Biederman wrote:
>
> >> +static int do_wait_pid(struct wait_opts *wo)
> >> +{
> >> +	struct task_struct *target = pid_task(wo->wo_pid, PIDTYPE_PID);
> >                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > This is subtle change in behavior.
> >
> > Today on the task->children list we only place thread group leaders.
>
> Shouldn't we allow waiting on clone children if __WALL or __WCLONE is set?

Don't confuse clone child with child's sub-thread.

Oleg.


  reply	other threads:[~2021-03-11 15:16 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-09 20:39 [PATCH v3] do_wait: make PIDTYPE_PID case O(1) instead of O(n) Jim Newsome
2021-03-10 17:27 ` Oleg Nesterov
2021-03-10 22:40 ` Eric W. Biederman
2021-03-11  0:14   ` Jim Newsome
2021-03-11 15:15     ` Oleg Nesterov [this message]
2021-03-11 16:26       ` Jim Newsome
2021-03-11 16:30     ` Eric W. Biederman
2021-03-11 15:08   ` Oleg Nesterov
2021-03-11 16:37     ` Eric W. Biederman

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