Re: [qvm86-devel] Tech. Description

[Paul Brook]

On Wednesday 06 April 2005 16:29, address@hidden wrote:
> Congratulation! Fine thing, thanks.
>
> Is it possible to get some technical insight of what this accelerator
> module does? Yes, I know, I can look it up in the source. But if somebody
> already knows, it would be much faster to get such a brief description.

qvm86 uses virtualization techniques for running ring3 (apllication/user-mode 
unprivileged) guest code. This basically means using the CPU MMU and 
protection mechanisms to run the the guest code unmodified.

Because the x86 CPU wasn't designed to be virtualized this isn't possible[1] 
for privileged kernel code, so we use the normal qemu dynamic translation 
emulate that code. 

Paul

[1] Some projects do virtualize kernel code, but this requires either 
modifying the guest code before it is executed (VMware), or using specially 
modified guest kernels (Xen).