Hi Paolo and all,

There are some question about the emulation for real mode in kvm/qemu. For
all the
question I suppose the 'unstrict guest' is not enabled.

1. how the protected mode CPU emulate the real mode? It seems it uses vm86,
however, vm86 is not available in x86_64 CPU? So what's the
'to_vmx(vcpu)->rmode.vm86_active' here vm86 means?

2. Does the guest's real mode code run directly in native CPU? It seems
'vmx->emulation_required' is also be false, it the vmx_vcpu_run will do a
switch to guest.

3. How the EPT work in guest real mode? The EPT is for GVA->GPA->HPA,
however there is no GVA, seems the identity mapping does something. But
there also some confusion for me. For example the real mode uses CS*4 + IP
to address the code.  Who does this calculation? In the kernel emulator?

Thanks,
Li Qiang

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