From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752056AbcCADAm (ORCPT ); Mon, 29 Feb 2016 22:00:42 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53034 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750800AbcCADAj (ORCPT ); Mon, 29 Feb 2016 22:00:39 -0500 Date: Mon, 29 Feb 2016 22:00:34 -0500 From: Jessica Yu To: Rusty Russell Cc: Jiri Kosina , Josh Poimboeuf , Seth Jennings , Vojtech Pavlik , Miroslav Benes , Petr Mladek , Steven Rostedt , Ingo Molnar , live-patching@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: livepatch/module: remove livepatch module notifier Message-ID: <20160301030034.GC12120@packer-debian-8-amd64.digitalocean.com> References: <1454993424-31031-1-git-send-email-jeyu@redhat.com> <1454993424-31031-5-git-send-email-jeyu@redhat.com> <87r3glzbzj.fsf@rustcorp.com.au> <87lh64e4tq.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <87lh64e4tq.fsf@rustcorp.com.au> X-OS: Linux eisen.io 3.16.0-4-amd64 x86_64 User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org +++ Rusty Russell [29/02/16 11:00 +1030]: >Jiri Kosina writes: >> On Wed, 10 Feb 2016, Rusty Russell wrote: >> >>> > Remove the livepatch module notifier in favor of directly enabling and >>> > disabling patches to modules in the module loader. Hard-coding the >>> > function calls ensures that ftrace_module_enable() is run before >>> > klp_module_coming() during module load, and that klp_module_going() is >>> > run before ftrace_release_mod() during module unload. This way, ftrace >>> > and livepatch code is run in the correct order during the module >>> > load/unload sequence without dependence on the module notifier call chain. >>> > >>> > This fixes a notifier ordering issue in which the ftrace module notifier >>> > (and hence ftrace_module_enable()) for coming modules was being called >>> > after klp_module_notify(), which caused livepatch modules to initialize >>> > incorrectly. >>> >>> Without a Fixes: line, it's not absolutely clear whether this needs >>> CC:stable, needs to go to Linus now, or can wait for the next merge >>> window. >>> >>> I *think* you want all four merged this merge window, and 3 and 4 are >>> required to fix a regression introduced since 4.4... >> >> Your understanding is correct; #3 and #4 are needed to fix a 4.4 >> regression. It makes sense for the whole lot go to together, but for #1 >> and #2 I absolutely need your Ack before I take it to my tree, as I don't >> want to be merging this behind your back. >> >> Once you Ack #1 and #2, I plan to take this to Linus immediately so that >> we avoid doing these changes as very last minute. > >Sorry Jiri, I am on paternity leave. Am happy with all these patches; >please use your best judgement: > >Acked-by: Rusty Russell > Thanks Rusty. No worries, we got the regression out of the way already. :-) Jiri, I'll resend the remaining 3 patches in the series separately, since we've merged the ftrace patch already. Jessica