根据1204_HWE-EOL，应该有升级到 12.04.5 HWE 的选项，但是，我没有收到来自hwe-support-status.
# uname -r
3.11.0-24-generic
# hwe-support-status --verbose
Your current Hardware Enablement Stack (HWE) is going out of support
on 08/07/2014. After this date security updates for critical parts (kernel
and graphics stack) of your system will no longer be available.
For more information, please see:
http://wiki.ubuntu.com/1204_HWE_EOL
To upgrade to a supported (or longer supported) configuration:
* Upgrade from Ubuntu 12.04 LTS to Ubuntu 14.04 LTS by running:
sudo do-release-upgrade -p
OR
* …