Messages in this thread | | | Date | Sun, 8 Mar 2009 23:06:09 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH] xen: core dom0 support |
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* H. Peter Anvin <hpa@zytor.com> wrote:
> Ingo Molnar wrote: > > > > Associativity effects do depend on the kernel image layout > > and on the precise allocations of kernel data structure > > allocations we do during bootup - and they dont really > > change after that. > > > > By the way, there is a really easy way (if a bit time > consuming) to get the actual variability here -- you have to > reboot between runs, even for the same kernel. It makes the > data collection take a long time, but at least it can be > scripted.
Since it's the same kernel image i think the only truly reliable method would be to reboot between _different_ kernel images: same instructions but randomly re-align variables both in terms of absolute address and in terms of relative position to each other. Plus randomize bootmem allocs and never-gets-freed-really boot-time allocations.
Really hard to do i think ...
Ingo
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