Ubuntu – Will it be possible to use a non-pae kernel in recent versions of Ubuntu


I know that Ubuntu +1 questions are frowned upon, but this I believe is a fair exception. Currently I have 2 systems running Ubuntu 12.10, and one of them has a Pentium M that doesn't support PAE (strange I know, but true).

This has meant in the past that I had to rely on a custom iso to install Ubuntu a similar system,and so this time I went with Xubuntu 12.04.

My question is 2 fold, but really one question:

  • Is it/will it be possible to install a non-pae version of the 12.10 kernel from the standard repositories?
  • If no, how can I get such a kernel? (Is there a PPA with such a kernel available?).


Before anyone suggests that I just install this package: http://packages.ubuntu.com/quantal/linux-image-generic, please note that this comes with PAE enabled.

P.S. Yes, I have Googled. I haven't found the answer.

Best Answer

It is possible to upgrade from 12.04 to 12.10 (and using the official new PAE kernels) by tricking apt-get into believing that your system has a pae enabled cpu (it will simply grep for "pae" in /proc/cpuinfo).

The affected early Pentium-M processors are missing this pae flag but are still capable of running these kernels if only the Ubuntu installers (or the preinst scripts of the kernel packages) would not try to be smarter than the user and actively prevent it from installing.

There is now an elegant and easy woraround for this problem: Before upgrading from 12.04 to 12.10 just patch the /proc/cpuinfo (can be done with a simple bindmount) and then do the distribution upgrade to 12.10 as usual.

There is a package "fake-pae" in this ppa that will do exactly this, just install that package and then do the dist-upgrade and soon after you will have a perfectly running 12.10 with 3.5 PAE kernel on your Pentium-M.