From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44E61C3402F for ; Mon, 17 Feb 2020 23:29:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2489520801 for ; Mon, 17 Feb 2020 23:29:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726155AbgBQX3u (ORCPT ); Mon, 17 Feb 2020 18:29:50 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:34977 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725927AbgBQX3u (ORCPT ); Mon, 17 Feb 2020 18:29:50 -0500 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1j3ppQ-0001U1-Uu; Tue, 18 Feb 2020 00:29:29 +0100 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id 4D4DA100292; Tue, 18 Feb 2020 00:29:27 +0100 (CET) From: Thomas Gleixner To: Christian Brauner , "Michael Kerrisk \(man-pages\)" Cc: Dmitry Safonov , Andrei Vagin , Linux Kernel , Dmitry Safonov <0x7f454c46@gmail.com>, Adrian Reber , Andy Lutomirski , Arnd Bergmann , Cyrill Gorcunov , "Eric W. Biederman" , "H. Peter Anvin" , Ingo Molnar , Jann Horn , Jeff Dike , Oleg Nesterov , Pavel Emelyanov , Shuah Khan , Vincenzo Frascino , containers , criu@openvz.org, Linux API , x86@kernel.org, Andrei Vagin Subject: Re: Time Namespaces: CLONE_NEWTIME and clone3()? In-Reply-To: <20200217230331.he6p5bs766zp6smx@wittgenstein> Date: Tue, 18 Feb 2020 00:29:27 +0100 Message-ID: <874kvossh4.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christian Brauner writes: > On Mon, Feb 17, 2020 at 10:47:53PM +0100, Michael Kerrisk (man-pages) wrote: >> Actually, I think the alternative you propose just here is better. I >> imagine there are times when one will want to create multiple >> namespaces with a single call to clone3(), including a time namespace. >> I think this should be allowed by the API. And, otherwise, clone3() >> becomes something of a second-class citizen for creating namespaces. >> (I don't really get the "less invasive" argument. Implementing this is >> just a piece of kernel to code to make user-space's life a bit simpler >> and more consistent.) > > I don't particularly mind either way. If there's actual users that need > to set it at clone3() time then we can extend it. So I'd like to hear > what Adrian, Dmitry, and Thomas think since they are well-versed how > this will be used in the wild. I'm weary of exposing a whole new uapi > struct and extending clone3() without any real use-case but I'm happy to > if there is! I really have no clue. I merily helped getting this in shape without creating havoc for timekeeping and VDSO. I have to punt to the container wizards. Thanks, tglx