If you are running Ubuntu and wish to gather profiling information
about your kernel, you will need to install the linux-image-debug
package corresponding to your running kernel version. Those packages
are large, and currently not available through the normal Ubuntu
package repositories. Instead, please go to

  http://ddebs.ubuntu.com/pool/main/l/linux/

and download the linux-image-debug corresponding to your
running kernel. The *.ddeb has to be installed via dpkg or gdebi.
