From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 688EEC07E96 for ; Thu, 8 Jul 2021 22:17:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3880561624 for ; Thu, 8 Jul 2021 22:17:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229866AbhGHWUP (ORCPT ); Thu, 8 Jul 2021 18:20:15 -0400 Received: from smtp01.belwue.de ([129.143.71.86]:48426 "EHLO smtp01.belwue.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229497AbhGHWUP (ORCPT ); Thu, 8 Jul 2021 18:20:15 -0400 Received: from fex.rus.uni-stuttgart.de (fex.rus.uni-stuttgart.de [129.69.1.129]) by smtp01.belwue.de (Postfix) with SMTP id 9A3FB6097 for ; Fri, 9 Jul 2021 00:17:31 +0200 (MEST) Date: Fri, 9 Jul 2021 00:17:31 +0200 From: Ulli Horlacher To: linux-btrfs@vger.kernel.org Subject: cannot use btrfs for nfs server Message-ID: <20210708221731.GB8249@tik.uni-stuttgart.de> Mail-Followup-To: linux-btrfs@vger.kernel.org References: <20210310074620.GA2158@tik.uni-stuttgart.de> <20210311074636.GA28705@tik.uni-stuttgart.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210311074636.GA28705@tik.uni-stuttgart.de> User-Agent: Mutt/1.5.23 (2014-03-12) Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org I have waited some time and some Ubuntu updates, but the bug is still there: On Thu 2021-03-11 (08:46), Ulli Horlacher wrote: > On Wed 2021-03-10 (08:46), Ulli Horlacher wrote: > > > When I try to access a btrfs filesystem via nfs, I get the error: > > > > root@tsmsrvi:~# mount tsmsrvj:/data/fex /nfs/tsmsrvj/fex > > root@tsmsrvi:~# time find /nfs/tsmsrvj/fex | wc -l > > find: File system loop detected; '/nfs/tsmsrvj/fex/spool' is part of the same file system loop as '/nfs/tsmsrvj/fex'. > > It is even worse: > > root@tsmsrvj:# grep localhost /etc/exports > /data/fex localhost(rw,async,no_subtree_check,no_root_squash) > > root@tsmsrvj:# mount localhost:/data/fex /nfs/localhost/fex > > root@tsmsrvj:# du -s /data/fex > 64282240 /data/fex > > root@tsmsrvj:# du -s /nfs/localhost/fex > du: WARNING: Circular directory structure. > This almost certainly means that you have a corrupted file system. > NOTIFY YOUR SYSTEM MANAGER. > The following directory is part of the cycle: > /nfs/localhost/fex/spool > > 0 /nfs/localhost/fex > > root@tsmsrvj:# btrfs subvolume list /data > ID 257 gen 42 top level 5 path fex > ID 270 gen 42 top level 257 path fex/spool > ID 271 gen 21 top level 270 path fex/spool/.snapshot/2021-03-07_1453.test > ID 272 gen 23 top level 270 path fex/spool/.snapshot/2021-03-07_1531.test > ID 273 gen 25 top level 270 path fex/spool/.snapshot/2021-03-07_1532.test > ID 274 gen 27 top level 270 path fex/spool/.snapshot/2021-03-07_1718.test root@tsmsrvj:~# uname -a Linux tsmsrvj 5.4.0-77-generic #86-Ubuntu SMP Thu Jun 17 02:35:03 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux root@tsmsrvj:~# btrfs version btrfs-progs v5.4.1 root@tsmsrvj:~# dpkg -l | grep nfs- ii nfs-common 1:1.3.4-2.5ubuntu3.4 amd64 NFS support files common to client and server ii nfs-kernel-server 1:1.3.4-2.5ubuntu3.4 amd64 support for NFS kernel server This makes btrfs with snapshots unusable as a nfs server :-( How/where can I escalate it further? My Ubuntu bug report has been ignored :-( https://bugs.launchpad.net/ubuntu/+source/nfs-utils/+bug/1918599 -- Ullrich Horlacher Server und Virtualisierung Rechenzentrum TIK Universitaet Stuttgart E-Mail: horlacher@tik.uni-stuttgart.de Allmandring 30a Tel: ++49-711-68565868 70569 Stuttgart (Germany) WWW: http://www.tik.uni-stuttgart.de/ REF:<20210311074636.GA28705@tik.uni-stuttgart.de>