Re: [RFC, PATCH 1/24] i386 Vmi documentation II

On Thursday 23 March 2006 00:54, Zachary Amsden wrote:
Andi Kleen wrote:
On Wednesday 22 March 2006 23:45, Zachary Amsden wrote:


I propose an entirely different approach - use segmentation.


That would require a lot of changes to save/restore the segmentation
register at kernel entry/exit since there is no swapgs on i386.
And will be likely slower there too and also even slow down the
VMI-kernel-no-hypervisor.


There are no changes required to the kernel entry / exit paths. With
save/restore segment support in the VMI, reserving one segment for the
hypervisor data area is easy.

Ok that might work yes.

Still might be the best option.

How did that rumoured Xenolinux-over-VMI implementation solve that problem?


!CONFIG_SMP -- as I believe I saw in the latest Xen patches sent out as
well?

Ah, cheating. This means the rumoured benchmark numbers are dubious too I guess.

-Andi
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