From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754741AbbCFOoB (ORCPT ); Fri, 6 Mar 2015 09:44:01 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53761 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752927AbbCFOn7 (ORCPT ); Fri, 6 Mar 2015 09:43:59 -0500 Date: Fri, 6 Mar 2015 08:43:20 -0600 From: Josh Poimboeuf To: Masami Hiramatsu Cc: Petr Mladek , Seth Jennings , Jiri Kosina , Vojtech Pavlik , live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, Rusty Russell , Miroslav Benes , mingo@kernel.org, mathieu.desnoyers@efficios.com, oleg@redhat.com, paulmck@linux.vnet.ibm.com, andi@firstfloor.org, rostedt@goodmis.org, tglx@linutronix.de Subject: Re: [PATCH 2/2] livepatch: fix patched module loading race Message-ID: <20150306144320.GA488@treble.redhat.com> References: <297cb260437910c43bf0ec85f53578f6cfef6d88.1425423640.git.jpoimboe@redhat.com> <20150304131752.GD15177@pathway.suse.cz> <54F7A8D9.7090808@hitachi.com> <20150305141845.GB1870@treble.redhat.com> <54F901CB.7060601@hitachi.com> <20150306105159.GJ15177@pathway.suse.cz> <54F99176.3090104@hitachi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <54F99176.3090104@hitachi.com> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 06, 2015 at 08:37:26PM +0900, Masami Hiramatsu wrote: > Actually, we can suppose this module unloading context is > not changing universe. thus it is expected behavior, isn't it? In the case of my proposed consistency model RFC, if the module unloading task gets preempted, or if mod->exit() calls schedule(), its task can switch to the new universe before it's done. And for many modules it could also be possible for other contexts to access the module's functions in the GOING state before mod->exit() disables them. -- Josh