nfs hangs after wakeup from hibernation, kernel 4.2.0-*

[Seved Torstendahl]

For a couple of years I have usually not shut down my pc after using it, I just leave it and let it hibernate.
(Of course I have also shut down the system completely every now and then.)
This has worked well but recently with new kernels 4.2.0-* I get problems that I suppose comes from nfs.
I have my firefox account and a folder in my PATH on a server with the file system automounted using nfs.
 - each new terminal window hangs without a prompt
 - a busybox terminal with a simpler PATH works ok
 - when I click on anything in the firefox window it hangs and is greyed-out. The system says "not responding" if I try to kill it

I have output from 'ps ax', ps -eF' and 'mount' commands that I will attach.
What more info do you need?

Regards,
Seved

---
ApportVersion: 2.19.1-0ubuntu5
Architecture: i386
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: seved 2509 F.... pulseaudio
CurrentDesktop: Unity
DistroRelease: Ubuntu 15.10
HibernationDevice: RESUME=UUID=38682e03-657e-46a8-b728-71bb6b19ffd3
InstallationDate: Installed on 2010-11-12 (1914 days ago)
InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release i386 (20100816.1)
MachineType: Gigabyte Technology Co., Ltd. G41M-ES2L
Package: linux (not installed)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.2.0-27-generic root=UUID=67935e67-5ba7-4442-8401-b0134d6ca21f ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 4.2.0-27.32-generic 4.2.8-ckt1
RelatedPackageVersions:
 linux-restricted-modules-4.2.0-27-generic N/A
 linux-backports-modules-4.2.0-27-generic N/A
 linux-firmware 1.149.3
RfKill:
 0: phy0: Wireless LAN
  Soft blocked: no
  Hard blocked: no
Tags: wily
Uname: Linux 4.2.0-27-generic i686
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm admin audio cdrom dialout lpadmin plugdev sambashare
_MarkForUpload: True
dmi.bios.date: 11/04/2009
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F6
dmi.board.name: G41M-ES2L
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF6:bd11/04/2009:svnGigabyteTechnologyCo.,Ltd.:pnG41M-ES2L:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnG41M-ES2L:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: G41M-ES2L
dmi.sys.vendor: Gigabyte Technology Co., Ltd.

[Seved Torstendahl (sevedt)]

The system where this happens is Ubuntu 15.10.
The server runs Ubuntu server 14.04.

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1543152/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1543152

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Seved Torstendahl (sevedt)]

The system is now in a half-locked state where anything that needs access to the server machine hangs.
I have temporarily removed the inclusion of a directory on the server from PATH (in .bashrc) which lets me start new terminal windows with bash, not only busybox.

However. when I tried explicit mounting from the nfs server the terminal hangs indefinitely which makes me believe that it is the mount command that should own the problem.

I attach some info from the failed attempts to run apport-collect.

After this I will restart the system and rerun apport-collect

[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

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[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

apport information

[Seved Torstendahl (sevedt)]

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[Seved Torstendahl (sevedt)]

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[Seved Torstendahl (sevedt)]

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[Seved Torstendahl (sevedt)]

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[Seved Torstendahl (sevedt)]

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[Seved Torstendahl (sevedt)]

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[Seved Torstendahl (sevedt)]

Actually I have misinterpreted the swedish terms, my system has been suspended when I see the symptoms.
I have checked hibernation also, it seems to be the same problem. But hibernation is not an option after inactivity.

I also wrote firefox when it really was thunderbird that I meant.

Further investigations show that it is automount that fails when :
1. a file is opened for writing on a nfs-mounted volume that autofs mounts
2. autofs unmount the nfs directory after five minutes of inactivity, AND
3. the system is automatically suspended after ten minutes of inactivity

After resuming activity it is impossible to access the volume on the server

To reproduce:
    cat > /path/to/file/on/automounted/nfs-dir/file.txt
    write some text
    wait for the system to suspend (setting in the power management, I chose ten minutes)

Activate the system again and try to access the automounted volume

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.5 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'.

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/v4.5-rc3-wily/