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=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 635C7C43613 for ; Thu, 20 Jun 2019 09:25:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4780E2084A for ; Thu, 20 Jun 2019 09:25:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726140AbfFTJZu convert rfc822-to-8bit (ORCPT ); Thu, 20 Jun 2019 05:25:50 -0400 Received: from coyote.holtmann.net ([212.227.132.17]:60599 "EHLO mail.holtmann.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725875AbfFTJZu (ORCPT ); Thu, 20 Jun 2019 05:25:50 -0400 Received: from marcel-macpro.fritz.box (p4FEFC3D2.dip0.t-ipconnect.de [79.239.195.210]) by mail.holtmann.org (Postfix) with ESMTPSA id 4FFC9CEFA2; Thu, 20 Jun 2019 11:34:16 +0200 (CEST) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Subject: Re: Bluetooth regression breaking BT connection for all 2.0 and older devices in 5.0.15+, 5.1.x and master From: Marcel Holtmann In-Reply-To: <20190613073518.GA16436@kroah.com> Date: Thu, 20 Jun 2019 11:25:48 +0200 Cc: Hans de Goede , "open list:BLUETOOTH DRIVERS" , Jeremy Cline , Linux Kernel Mailing List Content-Transfer-Encoding: 8BIT Message-Id: <99BA793B-E069-4974-8194-5C69616109FA@holtmann.org> References: <20190613073518.GA16436@kroah.com> To: Greg Kroah-Hartman X-Mailer: Apple Mail (2.3445.104.11) Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org Hi Greg, >> First of all this is a known issue and it seems a fix is in the works, >> but what I do not understand is why the commit causing this has not >> simply been reverted until the fix is done, esp. for the 5.0.x >> stable series where this was introduced in 5.0.15. >> >> The problem I'm talking about is commit d5bb334a8e17 ("Bluetooth: Align >> minimum encryption key size for LE and BR/EDR connections"): >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d5bb334a8e171b262e48f378bd2096c0ea458265 >> basically completely breaking all somewhat older (and some current cheap >> no-name) bluetooth devices: >> >> A revert of this was first proposed on May 22nd: >> https://lore.kernel.org/netdev/CA+E=qVfopSA90vG2Kkh+XzdYdNn=M-hJN_AptW=R+B5v3HB9eA@mail.gmail.com/T/ >> We are 18 days further now and this problem still exists, including in the >> 5.0.15+ and 5.1.x stable kernels. >> >> A solution has been suggested: https://lore.kernel.org/linux-bluetooth/20190522070540.48895-1-marcel@holtmann.org/T/#u >> and at least the Fedora 5.1.4+ kernels now carry this as a temporary fix, >> but as of today I do not see a fix nor a revert in Torvald's tree yet and >> neither does there seem to be any fix in the 5.0.x and 5.1.x stable series. >> >> In the mean time we are getting a lot of bug reports about this: >> https://bugzilla.kernel.org/show_bug.cgi?id=203643 >> https://bugzilla.redhat.com/show_bug.cgi?id=1711468 >> https://bugzilla.redhat.com/show_bug.cgi?id=1713871 >> https://bugzilla.redhat.com/show_bug.cgi?id=1713980 >> >> And some reporters: >> https://bugzilla.redhat.com/show_bug.cgi?id=1713871#c4 >> Are indicating that the Fedora kernels with the workaround included >> still do not work... >> >> As such I would like to suggest that we just revert the troublesome >> commit for now and re-add it when we have a proper fix. > > I've now reverted this as it does not seem to be going anywhere anytime > soon. After the mess gets sorted out in Linus's tree, if someone could > send stable@vger the commit ids that should be applied, I will be glad > to do so. this took a while to get fixed since some of the is really old code. I just posted a fix that I think covers all corner cases. https://lore.kernel.org/linux-bluetooth/20190620091731.5823-1-marcel@holtmann.org/T/#u If I can get a few people to test this, that would be great. Thanks. Regards Marcel