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Date:   Tue, 10 Oct 2023 17:08:08 -0700
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Subject: Re: [PATCH v4 01/12] KVM: x86/mmu: helpers to return if KVM honors
 guest MTRRs
From:   Sean Christopherson <seanjc@google.com>
To:     Yan Zhao <yan.y.zhao@intel.com>
Cc:     Like Xu <like.xu.linux@gmail.com>, pbonzini@redhat.com,
        chao.gao@intel.com, kai.huang@intel.com,
        robert.hoo.linux@gmail.com, yuan.yao@linux.intel.com,
        kvm list <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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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