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Biederman" , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Tycho Andersen Subject: Re: [RFC 1/3] pidfd: allow pidfd_open() on non-thread-group leaders References: <20231130163946.277502-1-tycho@tycho.pizza> <874jh3t7e9.fsf@oldenburg.str.redhat.com> Date: Thu, 30 Nov 2023 20:43:18 +0100 In-Reply-To: (Mathieu Desnoyers's message of "Thu, 30 Nov 2023 14:00:01 -0500") Message-ID: <87ttp3rprd.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.3 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Thu, 30 Nov 2023 11:43:29 -0800 (PST) * Mathieu Desnoyers: >>> I'd like to offer a userspace API which allows safe stashing of >>> unreachable file descriptors on a service thread. >> By "safe" here do you mean not accessible via pidfd_getfd()? No, unreachable by close/close_range/dup2/dup3. I expect we can do an intra-process transfer using /proc, but I'm hoping for something nicer. Thanks, Florian