Re: [PATCH] KVM: x86/mmu: Guard against collision with KVM-defined PFERR_IMPLICIT_ACCESS

[Sean Christopherson]

On Fri, 21 Jul 2023 15:37:11 -0700, Sean Christopherson wrote:
> Add an assertion in kvm_mmu_page_fault() to ensure the error code provided
> by hardware doesn't conflict with KVM's software-defined IMPLICIT_ACCESS
> flag.  In the unlikely scenario that future hardware starts using bit 48
> for a hardware-defined flag, preserving the bit could result in KVM
> incorrectly interpreting the unknown flag as KVM's IMPLICIT_ACCESS flag.
> 
> WARN so that any such conflict can be surfaced to KVM developers and
> resolved, but otherwise ignore the bit as KVM can't possibly rely on a
> flag it knows nothing about.
> 
> [...]

Applied to kvm-x86 mmu, thanks!

[1/1] KVM: x86/mmu: Guard against collision with KVM-defined PFERR_IMPLICIT_ACCESS
      https://github.com/kvm-x86/linux/commit/3e90c27b4209

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