Martin Bligh came up with a simple way to fix the kernel
to enable kexec boot from any CPU. 

Rather than picking up boot cpu information from the MP 
tables (which belong to the previous boot in the case of 
kexec), it just sets it to the cpu its starting on.
(See the changes in arch/i386/kernel/smpboot.c)

This simplifies the the kexec-hwfixes patch, since we
no longer need to move to the boot cpu before stopping
other processors. Which removes a lot of the unconditional
patching of reboot.c and makes it less invasive, thanks to 
Martin. Also, at panic time, cpu migration is something 
that is best avoided.

It would be good if someone could test this out (on SMP)
and confirm it works fine (I tried it on a 4way).

Eric, Do these changes look OK to you ? Did you have
something similar in mind, when you were talking about
enabling the kexec'd kernel to not care about which cpu
it was running on ?

Regards
Suparna


-- 
Suparna Bhattacharya (suparna@in.ibm.com)
Linux Technology Center
IBM Software Labs, India