Comment 4 for bug 1508565

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Scott Moser (smoser) wrote : Re: maas uses 3.13 (hwe-t) kernel which does not work on IBM power

I did some investigation on option 'b' above. Attached is a bunch of doc on how i did that.

The summary is we can exploit bug 1508975 to make all maas ppc64el users to start getting hwe-v instead of hwe-t by default by deleting the 'com.ubuntu.maas.daily:v2:boot:14.04:amd64:hwe-t' from existance. The next time 'import' runs in maas, the 'hwe-v' kernel would be used for enlistment and commissioning.

That would have some interesting consequences, though:
i. Users will get systems installed with hwe-w.
  Curtin assumes booting with hwe-N means installation of hwe-N is desired.

ii. When hwe-w arrives it will automatically be used.
  I have not verified this, but I suspect that when 'hwe-w' arrives in stream data, then boot and enlistment would then magically move to using hwe-w, and then again with hwe-x. This assumption is based on the fact that my test deletion of hwe-t resulted in use of hwe-v rather than hwe-u (newest rather than oldest). I'
  That moving probably ends in hwe-x , and thus after 2016.05 as hwe-x is last kernel for trusty.

iii. Users who were happy with hwe-t (kvm guests) will need manual action for install of hwe-t
  As a user, the "hwe-kernel ride" above seems a necessary evil at best. However, its not necessary for those on virtual hardware. hwe-t works well there and as a result is probably the recommended path for a user in a virtual machine. Those users would now have to manually 'apt-get install linux-generic && reboot' after installation to get that kernel.