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 87205C433EF for ; Tue, 3 May 2022 11:55:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233357AbiECL7O (ORCPT ); Tue, 3 May 2022 07:59:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231882AbiECL7N (ORCPT ); Tue, 3 May 2022 07:59:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A6F0EB7F1; Tue, 3 May 2022 04:55:41 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 433176164E; Tue, 3 May 2022 11:55:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 902D0C385A9; Tue, 3 May 2022 11:55:39 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="iwmrY2Q1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1651578938; 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=OmnpymFgrKna+sorYsF9uO7087ZOoY3Nagqmgfgtvyw=; b=iwmrY2Q1Z5D2rGVAA265kMFcIFN0uJku1PhjnGHwvIhDRbrtY5xC0tE8RmF9AHg2cdbv7X w59MpGC2fCz7GMwqv2ef6Sdw1MNYtmmiBTK0+d7veygZHmULjs9O1XX1mOc32pN4ewyMF8 YoCyXu/14vRA+o3aNNd5wpIVEN/3Yn8= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 8fcc1fbf (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO); Tue, 3 May 2022 11:55:38 +0000 (UTC) Date: Tue, 3 May 2022 13:55:35 +0200 From: "Jason A. Donenfeld" To: Lennart Poettering Cc: Alexander Graf , linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, Dominik Brodowski , Greg Kroah-Hartman , Theodore Ts'o , Colm MacCarthaigh , Torben Hansen , Jann Horn Subject: Re: [PATCH 2/2] random: add fork_event sysctl for polling VM forks Message-ID: References: <20220502140602.130373-1-Jason@zx2c4.com> <20220502140602.130373-2-Jason@zx2c4.com> <7a1cfd1c-9f0e-f134-e544-83ee6d3cd9c9@amazon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Tue, May 03, 2022 at 10:29:49AM +0200, Lennart Poettering wrote: > As mentioned earlier, I am not convinced sysctl is the right place for > this. sysctls are understood by most people as being the place for > tweaking kernel settings. This is not a kernel setting, but a > notification concept, and the way Jason defined it there's nothing to > read nor write, which strongly suggests to move it elsewhere, but not > /proc/sys/. I think I'm coming around to this view that having a sysctl return -ENODATA is weird. It makes `sysctl -a` always complain to stderr, for example, which seems bad. > > I can see attractiveness in providing the /run/fork-id directly from the > > kernel though, to remove the dependency on systemd for poll-less > > notification of libraries. > > I agree. I'm still not convinced there's value in having a counter or a UUID, but if you had to choose, would you prefer a counter or a UUID? It sounds like the former, because you see a use for distinguishing between zero and non-zero? Or did you finally agree with me that vmgenid isn't granular enough for that? Jason