Re: [PATCH v10 0/9] Linear Address Masking (LAM) KVM Enabling

[Sean Christopherson]

On Wed, Jul 19, 2023, Binbin Wu wrote:
> Binbin Wu (7):
>   KVM: x86/mmu: Use GENMASK_ULL() to define __PT_BASE_ADDR_MASK
>   KVM: x86: Add & use kvm_vcpu_is_legal_cr3() to check CR3's legality
>   KVM: x86: Use KVM-governed feature framework to track "LAM enabled"
>   KVM: x86: Virtualize CR3.LAM_{U48,U57}
>   KVM: x86: Introduce get_untagged_addr() in kvm_x86_ops and call it in
>     emulator
>   KVM: VMX: Implement and wire get_untagged_addr() for LAM
>   KVM: x86: Untag address for vmexit handlers when LAM applicable
> 
> Robert Hoo (2):
>   KVM: x86: Virtualize CR4.LAM_SUP
>   KVM: x86: Expose LAM feature to userspace VMM

Looks good, just needs a bit of re-organination.  Same goes for the LASS series.

For the next version, can you (or Zeng) send a single series for LAM and LASS?
They're both pretty much ready to go, i.e. I don't expect one to hold up the other
at this point, and posting a single series will reduce the probability of me
screwing up a conflict resolution or missing a dependency when applying.

Lastly, a question: is there a pressing need to get LAM/LASS support merged _now_?
E.g. are there are there any publicly available CPUs that support LAM and/or LASS?

If not, I'll wait until v6.7 to grab these, e.g. so that you don't have to rush
madly to turn around the next version, and so that I'm not trying to squeeze too
much stuff in just before the merge window.