Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail.avalus.com ([89.16.176.221]:49888 "EHLO mail.avalus.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754541AbaFNJnl (ORCPT ); Sat, 14 Jun 2014 05:43:41 -0400 Date: Sat, 14 Jun 2014 10:37:14 +0100 From: Alex Bligh Reply-To: Alex Bligh To: linux-nfs@vger.kernel.org cc: Alex Bligh Subject: Peculiarity in handling NFSv4 mount paths with fsid=0 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Sender: linux-nfs-owner@vger.kernel.org List-ID: I've discovered I think a peculiarity with handling mount paths with fsid=0. This is on Ubuntu Precise (old) but I've used 3.13 too with the same problem. I have an exports line like this: /storage/local *(rw,sync,wdelay,nohide,crossmnt,insecure,no_root_squash,no_all_squash,no_subtree_check,secure_locks,acl,fsid=0,anonuid=65534,anongid=65534) And mounted a directory like this (which succeeded) # mount -t nfs4 10.157.208.1:nfs-01 /mnt And unmount did this: # umount 10.157.208.1:nfs-01 /mnt was not found in /proc/mounts /mnt was not found in /proc/mounts Examination showed /proc/mounts contained the line: 10.157.208.1:/nfs-01 /mnt nfs4 rw,relatime,vers=4.0,rsize=262144,wsize=262144,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=10.157.208.1,local_lock=none,addr=10.157.208.1 0 0 Whereas the outptut of 'mount' contained the line: 10.157.208.1:nfs-01 on /mnt type nfs4 (rw,addr=10.157.208.1,clientaddr=10.157.208.1) There is a difference here between "/nfs-01" and "nfs-01". This might merely be an annoying bug, where it not for the fact that as far as I can tell the mount is now cannot be unmounted with userspace tools. No amount of --fake and -n appears to help. System reset required. Of course had I typed: # mount -t nfs4 10.157.208.1:/nfs-01 /mnt all would have been well. I suspect something should be canonicalising the path consistently. -- Alex Bligh