Navigating folders which include network shares in the folder structure can cause an application to freeze

[Paul White]

The following is from Launchpad Questions:

My CIFS network mount under Ubuntu 11.10 (Oneiric Ocelot) will freeze without much obvious reason. Idling for an extensive time is the only thing I can think of. Found many similar reports, eg:

http://www.centos.org/modules/newbb/print.php?form=1&topic_id=35154&forum=55&order=ASC&start=0
http://serverfault.com/questions/307636/virtualbox-running-fedora-15-keeps-losing-its-cifs-mount-of-a-windows-share

My symptom is, I am able to mount the CIFS Network drive fine. I can write to it and read from it, for quite a while. The problem is that eventually the mount will become inaccessible from linux.

When that happens I can't run ls /mnt/z. Even sudo umount -l /mnt/zdoesn't work. In fact, when I run those commands they lock up the shell in which they were run.

dmesg gives the following error

[ 72.250743] CIFS VFS: default security mechanism requested. The default security mechanism will be upgraded from ntlm to ntlmv2 in kernel release 3.1
[ 126.807829] EXT4-fs (sda1): re-mounted. Opts: errors=remount-ro,commit=0
[ 288.336825] hrtimer: interrupt took 4463392 ns
[ 2036.256098] EXT4-fs (sda1): re-mounted. Opts: errors=remount-ro,commit=0
[ 3622.991531] CIFS VFS: Server corpfs1 has not responded in 300 seconds. Reconnecting...
[ 4722.294174] CIFS VFS: Unexpected lookup error -512
[ 4782.585254] CIFS VFS: Unexpected lookup error -512
[ 4855.705273] CIFS VFS: Unexpected lookup error -512

The reason that I suspect that idling for an extensive time is the culprit is that I can see that the system seems to have recovered from some kind of sleep mode, and remounting my prime HD (sda1). But I'm not sure.

Here are more info of my system:

$ uname -rm
3.0.0-17-generic x86_64

$ modinfo /lib/modules/3.0.0-17-generic/kernel/fs/cifs/cifs.ko
filename: /lib/modules/3.0.0-17-generic/kernel/fs/cifs/cifs.ko
version: 1.74
. . .
vermagic: 3.0.0-17-generic SMP mod_unload modversions

The ubuntu is running under virtualbox on my Windows 7 machine. the network is always working on the Windows side.

Just logging what I am experiencing, and understand that there may not be any solution.
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My own experience is that when downloading files using Opera and trying to navigate the file system in order to find the directory in which I wish to save the file, freezes Opera. If I try to open or save a file using a text editor, say gVim, then a similar problem is encountered. The freeze doesn't happen every time. I can't seem to work out why I experience a freeze only some of the time. Any freeze may last several minutes.

I am only seeing this with Kubuntu 12.10 and 13.04. I did not see this with Ubuntu/Kubuntu 12.04.

Disconnecting my NAS drive allows me to open and save files to any directory without any freezing at all.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Oliver Dumschat-Hötte (o-dumschatt-hoette)]

Same problem on Ubuntu 12.04.2 LTS/Kernel 3.5.0.22.29/lts-quantal , Fedora 17/Kernel 3.8.4-102/x86_64 and 3.6.2-4/i686, similar problem on Debian 6/Kernel 2.6.32-5-amd64 (CIFS VFS: No writable handles for inode), ... all installed on plain hardware.
So this seems not to be a VirtualBox-Problem as stated in another thread and also not a problem of a special kernel version, architecture or distribution.

Not seen on Ubuntu 12.04.2 LTS/Kernel 3.2.0-31-generic/i686 until now.

[Jelmer Vernooij (jelmer)]

This is a bug in the linux cifsfs kernel module.

[Joseph Salisbury (jsalisbury)]

Did this issue occur in a previous version of Ubuntu, or is this a new issue?

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.16 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.16-rc6-utopic/

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]