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=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 7A575C4338F for ; Thu, 19 Aug 2021 20:05:28 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 042AE610E6 for ; Thu, 19 Aug 2021 20:05:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 042AE610E6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=1wt.eu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 7B1436B006C; Thu, 19 Aug 2021 16:05:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 73AD98D0001; Thu, 19 Aug 2021 16:05:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5DB226B0072; Thu, 19 Aug 2021 16:05:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0162.hostedemail.com [216.40.44.162]) by kanga.kvack.org (Postfix) with ESMTP id 3EBB96B006C for ; Thu, 19 Aug 2021 16:05:27 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id DDA1227748 for ; Thu, 19 Aug 2021 20:05:26 +0000 (UTC) X-FDA: 78492909852.08.529F1B9 Received: from 1wt.eu (wtarreau.pck.nerim.net [62.212.114.60]) by imf13.hostedemail.com (Postfix) with ESMTP id E9C2F100E17F for ; Thu, 19 Aug 2021 20:05:25 +0000 (UTC) Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id 17JK3N5l013157; Thu, 19 Aug 2021 22:03:23 +0200 Date: Thu, 19 Aug 2021 22:03:23 +0200 From: Willy Tarreau To: Jeff Layton Cc: Rodrigo Campos , "Eric W. Biederman" , Matthew Wilcox , Andy Lutomirski , Linus Torvalds , David Laight , David Hildenbrand , Linux Kernel Mailing List , Andrew Morton , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Al Viro , Alexey Dobriyan , Steven Rostedt , "Peter Zijlstra (Intel)" , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Petr Mladek , Sergey Senozhatsky , Andy Shevchenko , Rasmus Villemoes , Kees Cook , Greg Ungerer , Geert Uytterhoeven , Mike Rapoport , Vlastimil Babka , Vincenzo Frascino , Chinwen Chang , Michel Lespinasse , Catalin Marinas , Huang Ying , Jann Horn , Feng Tang , Kevin Brodsky , Michael Ellerman , Shawn Anastasio , Steven Price , Nicholas Piggin , Christian Brauner , Jens Axboe , Gabriel Krisman Bertazi , Peter Xu , Suren Baghdasaryan , Shakeel Butt , Marco Elver , Daniel Jordan , Nicolas Viennot , Thomas Cedeno , Collin Fijalkovich , Michal Hocko , Miklos Szeredi , Chengguang Xu , Christian =?iso-8859-1?Q?K=F6nig?= , "linux-unionfs@vger.kernel.org" , Linux API , the arch/x86 maintainers , "" , Linux-MM , Florian Weimer , Michael Kerrisk Subject: Re: Removing Mandatory Locks Message-ID: <20210819200323.GA13017@1wt.eu> References: <87eeay8pqx.fsf@disp2133> <5b0d7c1e73ca43ef9ce6665fec6c4d7e@AcuMS.aculab.com> <87h7ft2j68.fsf@disp2133> <87k0kkxbjn.fsf_-_@disp2133> <8ba92aa3e97bfc3df89cd64fffcbc91b640530f1.camel@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8ba92aa3e97bfc3df89cd64fffcbc91b640530f1.camel@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) Authentication-Results: imf13.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf13.hostedemail.com: domain of w@1wt.eu designates 62.212.114.60 as permitted sender) smtp.mailfrom=w@1wt.eu X-Stat-Signature: 6qpri5eoide9st3xjnzi1uouierzomi9 X-Rspamd-Queue-Id: E9C2F100E17F X-Rspamd-Server: rspam05 X-HE-Tag: 1629403525-864365 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Aug 19, 2021 at 03:18:15PM -0400, Jeff Layton wrote: > On Wed, 2021-08-18 at 11:34 +0200, Rodrigo Campos wrote: > > On Tue, Aug 17, 2021 at 6:49 PM Eric W. Biederman wrote: > > > > > > Matthew Wilcox writes: > > > > > > > On Fri, Aug 13, 2021 at 05:49:19PM -0700, Andy Lutomirski wrote: > > > > > [0] we have mandatory locks, too. Sigh. > > > > > > > > I'd love to remove that. Perhaps we could try persuading more of the > > > > distros to disable the CONFIG option first. > > > > > > Yes. The support is disabled in RHEL8. > > > > If it helps, it seems to be enabled on the just released debian stable: > > $ grep CONFIG_MANDATORY_FILE_LOCKING /boot/config-5.10.0-8-amd64 > > CONFIG_MANDATORY_FILE_LOCKING=y > > > > Also the new 5.13 kernel in experimental has it too: > > $ grep CONFIG_MANDATORY_FILE_LOCKING /boot/config-5.13.0-trunk-amd64 > > CONFIG_MANDATORY_FILE_LOCKING=y > > A pity. It would have been nice if they had turned it off a while ago. I > guess I should have done more outreach at the time. Sigh... Would it be acceptable to add a warning when MS_MANDLOCK is passed to mount() and backport this to stable kernels in order to get reports of any such use in a reasonably short time ? Anyway it sounds important to at least warn about deprecation. Willy