Comment 12 for bug 1414494

Looks like today's ubuntu updates fixed the bug, which is strange. The /var/log/apt/history.log entry produced by the update is:

Start-Date: 2015-02-03 22:51:31
Commandline: aptdaemon role='role-commit-packages' sender=':1.136'
Install: linux-image-extra-3.13.0-45-generic:amd64 (3.13.0-45.74), linux-image-3.13.0-45-generic:amd64 (3.13.0-45.74), linux-headers-3.13.0-45-generic:amd64 (3.13.0-45.74), linux-headers-3.13.0-45:amd64 (3.13.0-45.74)
Upgrade: linux-headers-generic:amd64 (3.13.0.44.51, 3.13.0.45.52), python3-software-properties:amd64 (0.92.37.2, 0.92.37.3), unzip:amd64 (6.0-9ubuntu1.1, 6.0-9ubuntu1.2), software-properties-common:amd64 (0.92.37.2, 0.92.37.3), linux-libc-dev:amd64 (3.13.0-44.73, 3.13.0-45.74), software-properties-gtk:amd64 (0.92.37.2, 0.92.37.3), linux-image-generic:amd64 (3.13.0.44.51, 3.13.0.45.52), linux-generic:amd64 (3.13.0.44.51, 3.13.0.45.52)
End-Date: 2015-02-03 22:53:23

At first glance, I thought that the 3.13.0-45 kernel version fixed it. But then I rebooted into kernel version 3.13.0-44, and couldn't reproduce the original bug, neither. What caused the bug and what solved it?