[PATCH 0/7] smp/hotplug rework / lockdep annotate

[Peter Zijlstra]

These here patches rework the cpu hotplug state machine and add
two lockdep (crossrelease) annotations.

The rework is quite invasive, but was suggested by Thomas as being the right
way to go about doing things :-)

These patches have been tested with Steve's hotplug stress script, as well as
two new hotplug test scripts which test cpu up/down rollback through explicit
failure injection (see last patch).

Where cpu-down used to insta-trigger a lockdep splat, I am no longer able to
trigger anything with these patches applied.