From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751403AbcCACGA (ORCPT ); Mon, 29 Feb 2016 21:06:00 -0500 Received: from ozlabs.org ([103.22.144.67]:57866 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751255AbcCACF7 (ORCPT ); Mon, 29 Feb 2016 21:05:59 -0500 From: Rusty Russell To: Jiri Kosina Cc: Jessica Yu , 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: [PATCH v4 4/4] livepatch/module: remove livepatch module notifier In-Reply-To: References: <1454993424-31031-1-git-send-email-jeyu@redhat.com> <1454993424-31031-5-git-send-email-jeyu@redhat.com> <87r3glzbzj.fsf@rustcorp.com.au> User-Agent: Notmuch/0.20.2 (http://notmuchmail.org) Emacs/24.5.1 (x86_64-pc-linux-gnu) Date: Mon, 29 Feb 2016 11:00:09 +1030 Message-ID: <87lh64e4tq.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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.