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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 450A7EB64D7 for ; Wed, 28 Jun 2023 15:56:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231417AbjF1P4M (ORCPT ); Wed, 28 Jun 2023 11:56:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:41473 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232032AbjF1Pz6 (ORCPT ); Wed, 28 Jun 2023 11:55:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1687967708; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=9qZSFuxG0IoUAkOzLqBAsv4mqf5Nr+aL9HVwyHW9Zro=; b=RcpICQjNprk2iI6SU6M5tUF4m57sSbeUtNESUqUPi93RbW90unkcPSEu3ESdNt5Z3NMwYY Gtg+096xyUzS9g+DOY/1H5jE4AMK6tAJSyP8VNSSzzh8psBWvPSouvtxxPONtml9Rgs5Zd qrVjMl1Wdwfe6l+Csiv0q33TfonVpcg= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-375-zxQD8_t6NrCMSLSlLOuOGA-1; Wed, 28 Jun 2023 11:54:53 -0400 X-MC-Unique: zxQD8_t6NrCMSLSlLOuOGA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D3320280D21A; Wed, 28 Jun 2023 15:54:05 +0000 (UTC) Received: from segfault.boston.devel.redhat.com (segfault.boston.devel.redhat.com [10.19.60.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5CC97111F3B6; Wed, 28 Jun 2023 15:54:05 +0000 (UTC) From: Jeff Moyer To: Matteo Rizzo Cc: Ricardo Ribalda , Bart Van Assche , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, io-uring@vger.kernel.org, jordyzomer@google.com, evn@google.com, poprdi@google.com, corbet@lwn.net, axboe@kernel.dk, asml.silence@gmail.com, akpm@linux-foundation.org, keescook@chromium.org, rostedt@goodmis.org, dave.hansen@linux.intel.com, chenhuacai@kernel.org, steve@sk2.org, gpiccoli@igalia.com, ldufour@linux.ibm.com Subject: Re: [PATCH 1/1] Add a new sysctl to disable io_uring system-wide References: <20230627120058.2214509-1-matteorizzo@google.com> <20230627120058.2214509-2-matteorizzo@google.com> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 Date: Wed, 28 Jun 2023 11:59:56 -0400 In-Reply-To: (Matteo Rizzo's message of "Wed, 28 Jun 2023 17:12:42 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Matteo Rizzo writes: > On Wed, 28 Jun 2023 at 13:44, Ricardo Ribalda wrote: >> >> Have you considered that the new sysctl is "sticky like kexec_load_disabled. >> When the user disables it there is no way to turn it back on until the >> system is rebooted. > > Are you suggesting making this sysctl sticky? Are there any examples of how to > implement a sticky sysctl that can take more than 2 values in case we want to > add an intermediate level that still allows privileged processes to use > io_uring? Also, what would be the use case? Preventing privileged processes > from re-enabling io_uring? See unprivileged_bpf_disabled for an example. I can't speak to the use case for a sticky value. -Jeff