Re: [RFC PATCH v3 46/59] KVM: VMX: Move register caching logic to common code

Thomas Gleixner
2021-11-25T20:12:46Z

On Wed, Nov 24 2021 at 16:20, isaku yamahata wrote:

> From: Sean Christopherson <sean.j.christopherson@intel.com>
>
> Move the guts of vmx_cache_reg() to vt_cache_reg() in preparation for
> reusing the bulk of the code for TDX, which can access guest state for
> debug TDs.
>
> Use kvm_x86_ops.cache_reg() in ept_update_paging_mode_cr0() rather than
> trying to expose vt_cache_reg() to vmx.c, even though it means taking a
> retpoline. The code runs if and only if EPT is enabled but unrestricted
> guest.

This sentence does not parse because it's not a proper sentence.

> Only one generation of CPU, Nehalem, supports EPT but not
> unrestricted guest, and disabling unrestricted guest without also
> disabling EPT is, to put it bluntly, dumb.

This one is only significantly better and lacks an explanation what this
means for the dumb case.

Thanks,

tglx