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Date:   Tue,  6 Jun 2023 17:55:02 -0700
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Subject: Re: [PATCH 0/3] KVM: x86: Use "standard" mmu_notifier hook for APIC page
From:   Sean Christopherson <seanjc@google.com>
To:     Sean Christopherson <seanjc@google.com>,
        Paolo Bonzini <pbonzini@redhat.com>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        Alistair Popple <apopple@nvidia.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Jason Gunthorpe <jgg@ziepe.ca>
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On Thu, 01 Jun 2023 18:15:15 -0700, Sean Christopherson wrote:
> Convert VMX's handling of mmu_notifier invalidations of the APIC-access page
> from invalidate_range() to KVM's standard invalidate_range_{start,end}().
> 
> KVM (ab)uses invalidate_range() to fudge around not stalling vCPUs until
> relevant in-flight invalidations complete.  Abusing invalidate_range() works,
> but it requires one-off code in KVM, sets a bad precedent in KVM, and is
> blocking improvements to mmu_notifier's definition of invalidate_range()
> due to KVM's usage diverging wildly from the original intent of notifying
> IOMMUs of changes to shared page tables.
> 
> [...]

Applied to kvm-x86 vmx, thanks!

[1/3] KVM: VMX: Retry APIC-access page reload if invalidation is in-progress
      https://github.com/kvm-x86/linux/commit/878940b33d76
[2/3] KVM: x86: Use standard mmu_notifier invalidate hooks for APIC access page
      https://github.com/kvm-x86/linux/commit/0a8a5f2c8c26
[3/3] KVM: x86/mmu: Trigger APIC-access page reload iff vendor code cares
      https://github.com/kvm-x86/linux/commit/0a3869e14d4a

--
https://github.com/kvm-x86/linux/tree/next
https://github.com/kvm-x86/linux/tree/fixes