Re: [PATCH v4 01/12] KVM: x86/mmu: helpers to return if KVM honors guest MTRRs

From: Yan Zhao
Date: Tue Oct 10 2023 - 22:15:49 EST


On Tue, Oct 10, 2023 at 05:08:08PM -0700, Sean Christopherson wrote:
> On Tue, Oct 10, 2023, Yan Zhao wrote:
> > BTW, as param "kvm" is now removed from the helper, better to remove the word
> > "second" in comment in patch 4, i.e.
> >
> > - * So, specify the second parameter as true here to indicate
> > - * non-coherent DMAs are/were involved and TDP zap might be
> > - * necessary.
> > + * So, specify the parameter as true here to indicate non-coherent
> > + * DMAs are/were involved and TDP zap might be necessary.
> >
> > Sorry and thanks a lot for helps on this series!
>
> Heh, don't be sorry, it's not your fault I can't get this quite right. Fixed
> up yet again, hopefully for the last time. This is what I ended up with for the
> comment:
>
> /*
> * Non-coherent DMA assignment and de-assignment will affect
> * whether KVM honors guest MTRRs and cause changes in memtypes
> * in TDP.
> * So, pass %true unconditionally to indicate non-coherent DMA was,
> * or will be involved, and that zapping SPTEs might be necessary.
> */
>
> and the hashes:
>
> [1/5] KVM: x86/mmu: Add helpers to return if KVM honors guest MTRRs
> https://github.com/kvm-x86/linux/commit/1affe455d66d
> [2/5] KVM: x86/mmu: Zap SPTEs when CR0.CD is toggled iff guest MTRRs are honored
> https://github.com/kvm-x86/linux/commit/7a18c7c2b69a
> [3/5] KVM: x86/mmu: Zap SPTEs on MTRR update iff guest MTRRs are honored
> https://github.com/kvm-x86/linux/commit/9a3768191d95
> [4/5] KVM: x86/mmu: Zap KVM TDP when noncoherent DMA assignment starts/stops
> https://github.com/kvm-x86/linux/commit/362ff6dca541
> [5/5] KVM: VMX: drop IPAT in memtype when CD=1 for KVM_X86_QUIRK_CD_NW_CLEARED
> https://github.com/kvm-x86/linux/commit/c9f65a3f2d92

Looks good to me, thanks!