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Message-ID: <544B7D9F.1070403@xmsnet.nl> Date: Sat, 25 Oct 2014 12:38:23 +0200 From: Hans de Bruin <jmdebruin@...net.nl> To: "Eric W. Biederman" <ebiederm@...ssion.com> CC: "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, linux-nfs@...r.kernel.org Subject: Re: 3.17.0+ files disappearing after playing old dos game on nfsroot laptop On 10/24/2014 08:18 PM, Eric W. Biederman wrote: > Hans de Bruin <jmdebruin@...net.nl> writes: > >> On 10/19/2014 07:32 PM, Hans de Bruin wrote: >>> On 10/15/2014 10:00 PM, Hans de Bruin wrote: >>>> After playing an old dos game i am missing files on my nfsroot installed >>>> laptop. Which one, wel /bin/ls is at least one of them. After a reboot >>>> there all back again. But not al is well. Some icons on my kde panel >>>> where gone. I have seen this twice in the last day's >>>> >>> >>> The problem appears immediately after starting dosemu so this bisectable >>> >> >> >> My bisect ended here: >> >> commit 8ed936b5671bfb33d89bc60bdcc7cf0470ba52fe >> Author: Eric W. Biederman <ebiederman@...tter.com> >> Date: Tue Oct 1 18:33:48 2013 -0700 >> >> >> vfs: Lazily remove mounts on unlinked files and directories. >> >> >> I haven reverted it yet. >> >> >> >> Eric, >> >> Immediately after starting dosemu all files under mount point /usr are >> gone. When I play a old dos game for a while (binaries are under /home) >> even /bin/ls disappears. Al mounts are nfs, even /. >> >> Could you look in to this and cc this to the relevant kernel >> mailinglist? > > At this point I don't know enough to reproduce this. > What does /proc/mounts look like before you start dosemu? bash-4.2$ cat /proc/mounts rootfs / rootfs rw 0 0 10.10.0.1:/nfs/root/psion_14.1 / nfs rw,relatime,vers=3,rsize=4096,wsize=4096,namlen=255,hard,nolock,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.10.0.1,mountvers=3,mountproto=tcp,local_lock=all,addr=10.10.0.1 0 0 devtmpfs /dev devtmpfs rw,relatime,size=1031016k,nr_inodes=220978,mode=755 0 0 proc /proc proc rw,relatime 0 0 sysfs /sys sysfs rw,relatime 0 0 tmpfs /run tmpfs rw,relatime,mode=755 0 0 devpts /dev/pts devpts rw,relatime,gid=5,mode=620 0 0 cgroup /sys/fs/cgroup cgroup rw,relatime,cpu 0 0 /dev/shm /tmp tmpfs rw,relatime,size=524288k 0 0 /dev/shm /dev/shm tmpfs rw,relatime,size=524288k 0 0 nfs:/nfs/usr/slackware-14.1/usr /usr nfs ro,relatime,vers=3,rsize=262144,wsize=262144,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.10.0.1,mountvers=3,mountport=38337,mountproto=udp,local_lock=none,addr=10.10.0.1 0 0 nfs:/nfs/home /home nfs rw,relatime,vers=3,rsize=262144,wsize=262144,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.10.0.1,mountvers=3,mountport=38337,mountproto=udp,local_lock=none,addr=10.10.0.1 0 0 nfs:/nfs/mp3 /mp3 nfs rw,relatime,vers=3,rsize=262144,wsize=262144,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.10.0.1,mountvers=3,mountport=38337,mountproto=udp,local_lock=none,addr=10.10.0.1 0 0 nfs:/nfs/src /usr/src nfs rw,relatime,vers=3,rsize=262144,wsize=262144,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.10.0.1,mountvers=3,mountport=38337,mountproto=udp,local_lock=none,addr=10.10.0.1 0 0 nfs:/nfs/video /video nfs rw,relatime,vers=3,rsize=262144,wsize=262144,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.10.0.1,mountvers=3,mountport=38337,mountproto=udp,local_lock=none,addr=10.10.0.1 0 0 I now know why I do not see any file in /usr after running dosemu. The whole /usr mount disappears in /proc/mounts. When I remount it I have a usable laptop again. Running dosemu a second time does not remove the mount again. In the mean time I have seen /usr disappear after running other programs like xterm and firefox. But until now never after remouting it. > > My expectation is that you should only see this if the mount points are > removed on the nfs server (which does not sound like it is the case). This is a at home environment with a nfs server in the meter cupboard. I have not changed the exports. > Although a transient malfunction of the nfs server or misplaced call to > check_submounts_and_drop could cause mounts to disappear as well. > During testing autofs was observed to have an inappropriate call I am not using autofs > to d_invalidate and it is unlikely but possible something like > that is going on with nfs as well. > > Are your nfs mounts read-only or read-write? /usr is mounted ro and exported ro > > What is your nfs-server and what is it exporting? > Which distro are you running? The nfs-server is slackware64 14.0 with a 3.4 kernel part from exports: /nfs/usr -ro,async,no_subtree_check 10.10.0.0/16 The laptop is slackware(32 bit) 14.1 with yesterday's linus kernel > Which version of dosemu are you running? 1.4.0.8 > How is dosemu configured to access files on your filesystem? I do not understand what you mean by this. It uses ~/.dosemu/drive_c -- Hans -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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