Re: [PATCH v1 3/4] KVM: VMX: Handle the immediate form of MSR instructions

[Chao Gao]

On Wed, Jul 30, 2025 at 10:46:04AM -0700, Xin Li (Intel) wrote:
>Handle two newly introduced VM exit reasons associated with the
>immediate form of MSR instructions.
>
>For proper virtualization of the immediate form of MSR instructions,
>Intel VMX architecture adds the following changes:

The CPUID feature bit also indicates support for the two new VM-exit reasons.
Therefore, KVM needs to reflect EXIT_REASON_MSR_READ/WRITE_IMM VM-exits to
L1 guests in nested cases if KVM claims it supports the new form of MSR
instructions.

I'm also wondering if the emulator needs to support this new instruction. I
suppose it does.