Comment 74 for bug 1304001

I think that this is a verification-failed. Upgrading the kernel in -proposed does not fix the issue:

ubuntu@ip-10-11-165-53:~$ uname -a
Linux ip-10-11-165-53 3.13.0-37-generic #64-Ubuntu SMP Mon Sep 22 21:28:38 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

ubuntu@ip-10-11-165-53:~$ dpkg-query --show linux-image-virtual
linux-image-virtual 3.13.0.37.44

ubuntu@ip-10-11-165-53:~$ dmesg | grep xen
[ 0.000000] xen: PV spinlocks enabled
[ 0.000000] xen:events: Xen HVM callback vector for event delivery is enabled
[ 0.440123] xen:balloon: Initialising balloon driver
[ 0.444026] xen_balloon: Initialising balloon driver
[ 0.452023] xen:balloon: Cannot add additional memory (-17)
[ 0.492062] Switched to clocksource xen
[ 0.515406] xen: --> pirq=16 -> irq=8 (gsi=8)
[ 0.515446] xen: --> pirq=17 -> irq=12 (gsi=12)
[ 0.515470] xen: --> pirq=18 -> irq=1 (gsi=1)
[ 0.515497] xen: --> pirq=19 -> irq=6 (gsi=6)
[ 0.515530] xen: --> pirq=20 -> irq=4 (gsi=4)
[ 0.778201] xen: --> pirq=21 -> irq=28 (gsi=28)
[ 0.778253] xen:grant_table: Grant tables using version 1 layout
[ 0.917639] xen_netfront: Initialising Xen virtual ethernet driver
[ 1.006714] xenbus_probe_frontend: Device with no driver: device/vfb/0
[ 2.456083] xen:balloon: Cannot add additional memory (-17)
[ 6.460080] xen:balloon: Cannot add additional memory (-17)
[ 14.476110] xen:balloon: Cannot add additional memory (-17)
[ 30.492059] xen:balloon: Cannot add additional memory (-17)
[ 62.556156] xen:balloon: Cannot add additional memory (-17)
[ 94.620107] xen:balloon: Cannot add additional memory (-17)