Re: [Qemu-devel] Re: KQEMU code organization

[Jamie Lokier <jamie@shareable.org>]

Avi Kivity wrote:
> kvm started out with qemu emulating 16-bit code (and before that, even 
> 32-bit code; kvm only did 64-bit).
> 
> The reason I don't like this approach is that it makes the interface 
> complex and hard to understand, and makes kvm heavily tied into qemu.
> 
> Some problems that arise from having qemu emulate code:
> - difficult to do smp properly

Now that atomic ops will be translated to atomic ops, and futex is
translated to host futex, and I think this is solved.

> - qemu needs to be able to inject mmio for in-kernel emulated devices
> - in-kernel devices (lapic, etc.) need to interact with guest code 
> executing in userspace

These two seem to apply equally if kqemu is made to work with
in-kernel emulated devices, which seems useful for exactly the same
reasons as kvm does.

-- Jamie