From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753330AbdJSNBu (ORCPT ); Thu, 19 Oct 2017 09:01:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38684 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751005AbdJSNBs (ORCPT ); Thu, 19 Oct 2017 09:01:48 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 7ACF1883BD Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=jpoimboe@redhat.com Date: Thu, 19 Oct 2017 08:01:46 -0500 From: Josh Poimboeuf To: Joao Moreira Cc: Miroslav Benes , live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, mmarek@suse.cz, pmladek@suse.com, jikos@suse.cz, nstange@suse.de, jroedel@suse.de, matz@suse.de, khlebnikov@yandex-team.ru, jeyu@kernel.org Subject: Re: [PATCH 0/8] livepatch: klp-convert tool Message-ID: <20171019130146.uxjuhgn2t3yavgz2@treble> References: <20170829190140.401-1-jmoreira@suse.de> <20170830180025.3s5tscqf5isqwg5n@treble> <20171011024615.y55lwbgpgo6b5dll@treble> <14124e34-04f7-950e-72fb-64f13e62f57e@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <14124e34-04f7-950e-72fb-64f13e62f57e@suse.de> User-Agent: Mutt/1.6.0.1 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Thu, 19 Oct 2017 13:01:48 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 11, 2017 at 09:42:09AM -0300, Joao Moreira wrote: > > Sounds good! For klp-convert to be successful, we really need a > > strategy for dealing with such optimizations. I'm thinking that a > > '-fpreserve-function-abi' flag would be the cleanest way to handle it. > > > > If we don't have a strategy for dealing with optimizations, then we may > > instead need to go with a binary diff-based tool like kpatch-build. > > I'm currently looking into binary diff-based solutions to deal with this > problem. My plan is to submit a second patch set once I have it functional > and land both things (klp-convert and bin-diff) in two different steps. Instead of having multiple approaches, I'd strongly prefer that we converge on a single in-tree approach that works for everybody. (Whether that will be source-based like klp-convert or binary-based like kpatch-build, I don't know.) BTW, what is bin-diff? Have you seen kpatch-build? > Is there any issue with following this schedule? Meaning, do you guys still > plan on reviewing this patch set or do you prefer me to do something > differently in terms of approach? IMO, klp-convert will only be useful if we have a realistic strategy for dealing with GCC optimizations. So I'd say we should follow through on that with the compiler folks before spending too much more time on it. -- Josh