Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2

["Roedel, Joerg" <Joerg.Roedel@amd.com>]

On Wed, Dec 01, 2010 at 06:38:30AM -0500, Nadav Har'El wrote:

> Can you please say a few words why you'd want to move this nested-exit
> request bit to x86.c?

I don't want to move the actual exit-code itself into generic code. This
code is different between svm and vmx. I think we could implement a
call-back in kvm_x86_ops which is called when a vmexit is requested.
The benefit is that we have a single and well-defined place where we
emulate a vmexit.
SVM already as a similar mechanism internally because nested_svm_vmexit
may sleep and can't be called from certain places. Another reason is
that emulating a vmexit at a wrong plase may have side-effects (for
example when called from within the instruction emulator).
With a generic request-bit I can remove the SVM internal implementation
and nested vmx could use it too. I am certain you will need something
similar in nested-vmx too. 

> Do you want to move some of the exit logic to x86.c - e.g., for the
> injection logic?

Thats another and probably more complex topic. I need a better
understanding of (nested-)vmx before we discuss how this can be done.
But a vmexit-callback may be helpful there as well.

	Joerg

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