From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail05.adl6.internode.on.net ([150.101.137.143]:18433 "EHLO ipmail05.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933117AbbI3V4n (ORCPT ); Wed, 30 Sep 2015 17:56:43 -0400 Date: Thu, 1 Oct 2015 07:56:40 +1000 From: Dave Chinner To: Roman Lebedev Cc: linux-btrfs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, fstests@vger.kernel.org Subject: Re: [RFC PATCH] fstests: generic: Test that fsync works on file in overlayfs merged directory Message-ID: <20150930215640.GH27164@dastard> References: <1443643065-16460-1-git-send-email-lebedev.ri@gmail.com> <1443643065-16460-2-git-send-email-lebedev.ri@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1443643065-16460-2-git-send-email-lebedev.ri@gmail.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Wed, Sep 30, 2015 at 10:57:45PM +0300, Roman Lebedev wrote: > As per overlayfs documentation, any activity on a merged directory > for a application that is doing such activity should work exactly > as if that would be a normal, non overlayfs-merged directory. > > That is, e.g. simple fopen-fwrite-fsync-fclose sequence should > work just fine. We have plenty of tests that do things like that. > But apparently it does not. Add a simple generic test to check that. > As of right now (linux-4.2.1) this test fails at least on btrfs. > > PS: An alternative (and probably better approach) would be to run > fstests test suite with TEST_DIR set to overlayfs work directory. Much better is to run xfstests directly on overlayfs. THere have been some patches to do that posted in the past, but those patches and discussions kinda ended up going nowhere: http://www.mail-archive.com/fstests@vger.kernel.org/msg00474.html Perhaps you'd like to pick this up, and then overlay will by much easier to test and hence likely not to have bugs like this... Cheers, Dave. -- Dave Chinner david@fromorbit.com