Re: [PATCH v2 1/3] kvm: x86: Introduce hypercall x86 ops for handling hypercall not in cpl0

[Yu Zhang]

On Thu, Sep 09, 2021 at 07:55:23PM +0800, Hou Wenlong wrote:
> Per Intel's SDM, use vmcall instruction in non VMX operation for cpl3
> it should trigger a #UD. And in VMX root operation, it should

Are you sure? IIRC, vmcall will always cause VM exit as long as CPU
is in non-root mode(regardless the CPL).

Also, could you please explain why skipping the vmcall would cause
exception in the host? Thanks!

B.R.
Yu