From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763271AbcLUKat (ORCPT ); Wed, 21 Dec 2016 05:30:49 -0500 Received: from helmsgagent01.f-secure.com ([193.110.108.21]:35995 "EHLO helmsgagent01.f-secure.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756552AbcLUKar (ORCPT ); Wed, 21 Dec 2016 05:30:47 -0500 X-Greylist: delayed 906 seconds by postgrey-1.27 at vger.kernel.org; Wed, 21 Dec 2016 05:30:47 EST From: Marko Rauhamaa To: Amir Goldstein CC: Jan Kara , Al Viro , Eric Paris , , Subject: Re: [RFC][PATCH 0/2] fsnotify: super block watch References: <1482247207-4424-1-git-send-email-amir73il@gmail.com> Date: Wed, 21 Dec 2016 12:15:26 +0200 In-Reply-To: <1482247207-4424-1-git-send-email-amir73il@gmail.com> (Amir Goldstein's message of "Tue, 20 Dec 2016 17:20:05 +0200") Message-ID: <87bmw5ziyp.fsf@drapion.f-secure.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux) 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 Amir Goldstein : > On the Oct 10 posting you asked me about the use case and it was hard > to explain the use case with only part of the work done. > > The issue, which this work sets to solve, is the poor scalability of > recursive inotify watches. On my [employer's] part, the fanotify API suffers from leakage through namespaces. If you need to monitor files in a filesystem, the current fanotify FAN_MARK_MOUNT flag does not give you a notification if you execute a command like unshare -m touch xyz inside the file system. Amir's patch addresses this increasingly critical issue. Marko