Re: [PATCH 1/2] KVM: x86: expand the LRU cache of previous CR3s

[Sean Christopherson <seanjc@google.com>]

KVM: x86/mmu:

On Tue, Oct 29, 2024, Yong He wrote:
> From: Yong He <alexyonghe@tencent.com>
> 
> Expand max number of LRU cache of previous CR3s, so that
> we could cache more entry when needed, such as KPTI is

No "we".  Documentation/process/maintainer-kvm-x86.rst

And I would argue this changelog is misleading.  I was expecting that the patch
would actually change the number of roots that KVM caches, whereas this simply
increases the capacity.  The changelog should also mention that the whole reason
for doing so is to allow for a module param.

Something like:

  KVM: x86/mmu: Expand max capacity of per-MMU CR3/PGD caches

  Expand the maximum capacity of the "previous roots" cache in kvm_mmu so
  that a future patch can make the number of roots configurable via module
  param, without needing to dynamically allocate the array.

That said, I hope we can avoid this entirely.  More in the next patch.