From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757015AbcANWyo (ORCPT ); Thu, 14 Jan 2016 17:54:44 -0500 Received: from mout.kundenserver.de ([217.72.192.73]:62584 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756980AbcANWym (ORCPT ); Thu, 14 Jan 2016 17:54:42 -0500 From: Arnd Bergmann To: y2038@lists.linaro.org Cc: Dave Chinner , linux-fsdevel@vger.kernel.org, Deepa Dinamani , linux-kernel@vger.kernel.org Subject: Re: [Y2038] [RFC 02/15] vfs: Change all structures to support 64 bit time Date: Thu, 14 Jan 2016 23:54:36 +0100 Message-ID: <4774139.hV6lmEpfqG@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <4096827.pGyVFmGqbD@wuerfel> References: <1452144972-15802-1-git-send-email-deepa.kernel@gmail.com> <20160114210000.GK6033@dastard> <4096827.pGyVFmGqbD@wuerfel> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:PVNCqYq9yjiy3dCw4Awgdf/ygx4Wb9g0SreVk8A5APhA2RYrpoi 2nMJdfciEzRMwKWV3v1cA/h89uzkFWoudJx96WAoyVDqR+ww9/32t9+gMc4tcQuKJ7Exafz IVo1R8EhxKyU4g0iXwHT+kCK4rDOQz1piRDbM33r9ah53hUJScM7jwCMw6z0T3ugYYmKq2A 94aXwNz9GOsvTuXR08RBw== X-UI-Out-Filterresults: notjunk:1;V01:K0:Y2rdQopw5IE=:pmIqOUtc4k8IjbLeFCnR4P N/LC70iogp1DP98qU0GA6qjQ8ltsyql9fVknmVE5qp1FMNXSxU4ohFZ9cD+DWoTX9sUEmImnh MBYzXLeLXSS52PzyEaRX/F8eYLRcnkrLgSpl3Nx3K3oNDWLkDBAk3kNIYlGfAvz3Aqe2RH/Ho th1Bz8NH0FW13kg8TRca6YB/1LjJIDmn87K9bgu02vsIf7RsqyoIJFIjoCgNGb/TtAh8uKUiW Asy1EaMDi6V28IJvXyx7ZpCI//BeJjF83TiYv/+6xE2OMC3hsELhgCRVsBUMPc82Bnk3M1I/G yRiPCjLj5TnCb0i569oFgXtLTvf+DoSMOeLpKpsWwtJ89QPq1p0uxLg/3A81Yp7WF8QdB6aTC xBhukz6AZ8Th4mM2TKWiQGZPJpaX+yRKS7W0GCd6dOkY9Dchg1/GvUySZHpwLy0viFlL9iGFn aLzhk8XwpQsAQujBInkk/95tQojZDN2cFZ+FElNmKPRvurBjee5IV/crnzSx4NSblXDUSbbRp tv93ykAQuO+rARCXorNFGj5s6RRDOs/wr/SEFXBoT4k7OVAAzqiyauV6Z+zZDudi966A6aa1+ 6Cr0PJOmdxHNHYIVuCyrRueedwclPerRvsX4liytQRLyokvZ/vX4z8ok0qu+zMKgVOGdKRKdF 4sHYYWRt9GqJgl5/Hk8VX2uTbVrwFiMJQaYRD2xi5hgXrMPeuaR9j6+j36AWFwjzzNtraTNjA Tlu4KVkRj2Q73l5I Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 14 January 2016 23:46:16 Arnd Bergmann wrote: > > I'm not following the line of thought here. We have some users > that want ext4 to mount old file system images without long > inodes writable, because they don't care about the 2038 problem. > We also have other users that want to force the same file system > image to be read-only because they want to ensure that it does > not stop working correctly when the time overflow happens while > the fs is mounted. > > If you don't want a compile-time option for it, how do you suggest > we decide which case we have? In case that came across wrong, I'm assuming that the first user also wants all the system calls enabled that pass 32-bit time_t values, while the second one wants them all left out from the kernel to ensure that no user space program gets incorrect data. This could be done using a sysctl of course, but I still think we want a compile-time option for the syscalls for clarity, and I would simply use the same compile-time option to determine the behavior of the file system, network protocols and device drivers that deal with 32-bit timestamps outside of the kernel. Arnd