Hangs with 1 CPU fully utilised after long period of suspend

[Phill]

Running 14.04 LTS Server in a virtual machine on a 14.04 LTS Desktop host.

When the guest suspends for a long period of time the guest server becomes unresponsive in both Virtual Machine Viewer and over SSH, with 100% of one CPU core utilised.

A hard reset of the guest is required.

The last entry in kern.log on the 14.04 guest seems to be the Clocksource complaint, the entry at 16:40 was the first entry following the hard reset:

Oct 14 22:16:18 syncthing kernel: [ 76.145297] random: nonblocking pool is initialized
Oct 14 22:23:12 syncthing kernel: [ 489.632956] Clocksource tsc unstable (delta = -2976366996 ns)
Oct 15 16:40:11 syncthing kernel: [ 0.000000] Initializing cgroup subsys cpuset

This was left overnight, but it's more typical for the machine to be suspended for a few hours, which still causes the problem.

I have many other 12.04 LTS Server guests that work just fine regardless of how long they are left suspended so this appears to be a regression.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-3.13.0-37-generic 3.13.0-37.64
ProcVersionSignature: Ubuntu 3.13.0-37.64-generic 3.13.11.7
Uname: Linux 3.13.0-37-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version k3.13.0-37-generic.
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
ApportVersion: 2.14.1-0ubuntu3.5
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path', '/dev/snd/controlC0', '/dev/snd/hwC0D0', '/dev/snd/pcmC0D0c', '/dev/snd/pcmC0D0p', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CRDA: Error: [Errno 2] No such file or directory: 'iw'
Card0.Amixer.info: Error: [Errno 2] No such file or directory: 'amixer'
Card0.Amixer.values: Error: [Errno 2] No such file or directory: 'amixer'
CurrentDmesg: [ 9.605618] random: nonblocking pool is initialized
Date: Wed Oct 15 16:49:06 2014
HibernationDevice: RESUME=/dev/mapper/ubuntu--1404--vg-swap_1
InstallationDate: Installed on 2014-10-13 (1 days ago)
InstallationMedia: Ubuntu-Server 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.3)
IwConfig:
 eth0 no wireless extensions.

 lo no wireless extensions.
Lsusb: Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
MachineType: QEMU Standard PC (i440FX + PIIX, 1996)
ProcFB: 0 cirrusdrmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.13.0-37-generic root=/dev/mapper/ubuntu--1404--vg-root ro
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-37-generic N/A
 linux-backports-modules-3.13.0-37-generic N/A
 linux-firmware 1.127.7
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 01/01/2011
dmi.bios.vendor: Bochs
dmi.bios.version: Bochs
dmi.chassis.type: 1
dmi.chassis.vendor: Bochs
dmi.modalias: dmi:bvnBochs:bvrBochs:bd01/01/2011:svnQEMU:pnStandardPC(i440FX+PIIX,1996):pvrpc-i440fx-trusty:cvnBochs:ct1:cvr:
dmi.product.name: Standard PC (i440FX + PIIX, 1996)
dmi.product.version: pc-i440fx-trusty
dmi.sys.vendor: QEMU

[Brad Figg (brad-figg)]

This change was made by a bot.

[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 v3.18 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/v3.18-rc1-utopic/

[Launchpad Janitor (janitor)]

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