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Wed, 24 Jan 2024 01:26:44 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 24 Jan 2024 02:25:32 +0100 (CET) Date: Wed, 24 Jan 2024 02:25:30 +0100 From: Oleg Nesterov To: Tycho Andersen Cc: Christian Brauner , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Tycho Andersen Subject: Re: [PATCH v3 1/3] pidfd: allow pidfd_open() on non-thread-group leaders Message-ID: <20240124012529.GC26412@redhat.com> References: <20240123153452.170866-1-tycho@tycho.pizza> <20240123153452.170866-2-tycho@tycho.pizza> <20240123195608.GB9978@redhat.com> <20240123222231.GA25162@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240123222231.GA25162@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 On 01/23, Oleg Nesterov wrote: > > But to be honest I can't understand test_non_tgl_poll_exit() at all. I don't > even understand why the process/thread created by fork_task_with_thread() > should ever exit. And why it creates the "writer" child... Never mind, too > late for me to read the code. Ah, OK, it passes thread_wait_exit to fork_task_with_thread(), and this "fn" reads sk_pair and does exit() which is actually exit_group(). Oleg.