[Bug 36158] Re: System does not power off on shutdown

[Sitsofe Wheeler]

If someone REALLY wants to have a shot at getting this fixed soon and it
really is a problem that only shows up in certain kernels (i.e. it
worked on some 2.6.15 kernels but not others) you can try selectively
compiling different kernels until the change that causes the problem is
narrowed down. It's a brute force attempt at tackling the issue and may
require dozens (or more) of kernels to compiled and tested. However if
you succeed in narrowing the problem down to a single patch you stand a
very good chance of having the problem fixed.

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System does not power off on shutdown
https://launchpad.net/bugs/36158