From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932937AbbCRTei (ORCPT ); Wed, 18 Mar 2015 15:34:38 -0400 Received: from mx2.parallels.com ([199.115.105.18]:41071 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750905AbbCRTeg (ORCPT ); Wed, 18 Mar 2015 15:34:36 -0400 Message-ID: <5509D342.7000403@parallels.com> Date: Wed, 18 Mar 2015 22:34:26 +0300 From: Pavel Emelyanov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Andrea Arcangeli , Linux Kernel Mailing List , Linux MM , Linux API CC: Sanidhya Kashyap Subject: [PATCH 0/3] UserfaultFD: Extension for non cooperative uffd usage Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [89.169.95.100] X-ClientProxiedBy: US-EXCH2.sw.swsoft.com (10.255.249.46) To US-EXCH.sw.swsoft.com (10.255.249.47) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On the recent LSF Andrea presented his userfault-fd patches and I had shown some issues that appear in usage scenarios when the monitor task and mm task do not cooperate to each other on VM changes (and fork()-s). Here's the implementation of the extended uffd API that would help us to address those issues. As proof of concept I've implemented only fix for fork() case, but I also plan to add the mremap() and exit() notifications, both are also required for such non-cooperative usage. More details about the extension itself is in patch #2 and the fork() notification description is in patch #3. Comments and suggestion are warmly welcome :) Andrea, what's the best way to go on with the patches -- would you prefer to include them in your git tree or should I instead continue with them on my own, re-sending them when required? Either way would be OK for me. Thanks, Pavel