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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 25906C43331 for ; Mon, 11 Nov 2019 12:31:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EDF312190F for ; Mon, 11 Nov 2019 12:31:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726978AbfKKMbV (ORCPT ); Mon, 11 Nov 2019 07:31:21 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:48188 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726946AbfKKMbV (ORCPT ); Mon, 11 Nov 2019 07:31:21 -0500 Received: from p54ac5540.dip0.t-ipconnect.de ([84.172.85.64] helo=wittgenstein) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1iU8qk-0000Ls-Tz; Mon, 11 Nov 2019 12:31:18 +0000 Date: Mon, 11 Nov 2019 13:31:18 +0100 From: Christian Brauner To: Arnd Bergmann Cc: y2038@lists.linaro.org, linux-kernel@vger.kernel.org, Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Geert Uytterhoeven , Christian Brauner , linux-api@vger.kernel.org Subject: Re: [PATCH 23/23] y2038: allow disabling time32 system calls Message-ID: <20191111123116.upuqpdetbxdmfp3i@wittgenstein> References: <20191108210236.1296047-1-arnd@arndb.de> <20191108211323.1806194-14-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20191108211323.1806194-14-arnd@arndb.de> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 08, 2019 at 10:12:22PM +0100, Arnd Bergmann wrote: > At the moment, the compilation of the old time32 system calls depends > purely on the architecture. As systems with new libc based on 64-bit > time_t are getting deployed, even architectures that previously supported > these (notably x86-32 and arm32 but also many others) no longer depend on > them, and removing them from a kernel image results in a smaller kernel > binary, the same way we can leave out many other optional system calls. > > More importantly, on an embedded system that needs to keep working > beyond year 2038, any user space program calling these system calls > is likely a bug, so removing them from the kernel image does provide > an extra debugging help for finding broken applications. > > I've gone back and forth on hiding this option unless CONFIG_EXPERT > is set. This version leaves it visible based on the logic that > eventually it will be turned off indefinitely. > > Signed-off-by: Arnd Bergmann Acked-by: Christian Brauner