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=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS 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 12423C433DB for ; Mon, 1 Mar 2021 08:08:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2F2664E46 for ; Mon, 1 Mar 2021 08:08:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232675AbhCAIHu (ORCPT ); Mon, 1 Mar 2021 03:07:50 -0500 Received: from mail.kernel.org ([198.145.29.99]:46764 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232748AbhCAIHq (ORCPT ); Mon, 1 Mar 2021 03:07:46 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id E4A1564E42; Mon, 1 Mar 2021 08:07:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614586026; bh=eYrKiRldcGd1/qq+sxHlcpmOrp2wd88rQgkH0JmzMWM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RvWeE1sPx0qe4txJaTyOiAnGuNX+mLLY4p8Do+UwiMsq18H8uw2VduUeZbCs29Yum UDihHV0SreF2nc73wquBoDwBM9FuwwQOmcImPUk83qQCcw3JZA17EIFSwYL+rxLmai HGZZ9+8pLgZyB1uNpKb1GCCsR50Orbvzp4SFlzuM= Date: Mon, 1 Mar 2021 09:07:03 +0100 From: Greg Kroah-Hartman To: Ben Hutchings Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, stable@vger.kernel.org, Lee Jones , "Luis Claudio R. Goncalves" , lwn@lwn.net, jslaby@suse.cz Subject: Re: futex breakage in 4.9 stable branch Message-ID: References: <161408880177110@kroah.com> <66826ac72356b00814f51487dd1008298e52ed9b.camel@decadent.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <66826ac72356b00814f51487dd1008298e52ed9b.camel@decadent.org.uk> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Mar 01, 2021 at 01:13:08AM +0100, Ben Hutchings wrote: > On Tue, 2021-02-23 at 15:00 +0100, Greg Kroah-Hartman wrote: > > I'm announcing the release of the 4.9.258 kernel. > > > > All users of the 4.9 kernel series must upgrade. > > > > The updated 4.9.y git tree can be found at: > >         git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-4.9.y > > and can be browsed at the normal kernel.org git web browser: > >          > > The backported futex fixes are still incomplete/broken in this version. > If I enable lockdep and run the futex self-tests (from 5.10): > > - on 4.9.246, they pass with no lockdep output > - on 4.9.257 and 4.9.258, they pass but futex_requeue_pi trigers a > lockdep splat > > I have a local branch that essentially updates futex and rtmutex in > 4.9-stable to match 4.14-stable. With this, the tests pass and lockdep > is happy. > > Unfortunately, that branch has about another 60 commits. Further, the > more we change futex in 4.9, the more difficult it is going to be to > update the 4.9-rt branch. But I don't see any better option available > at the moment. > > Thoughts? There were some posted futex fixes for 4.9 (and 4.4) on the stable list that I have not gotten to yet. Hopefully after these are merged (this week), these issues will be resolved. If not, then yes, they need to be fixed and any help you can provide would be appreciated. As for "difficulty", yes, it's rough, but the changes backported were required, for obvious reasons :( thanks, greg k-h