Re: [PATCH] KVM: X86: MMU: no mmu_notifier_seq++ in kvm_age_hva

Paolo Bonzini
2016-09-27T16:55:02Z

On 27/09/2016 17:31, Peter Feiner wrote:
>
> I'm reworking this function in a fix for nested bug exposed by PML.
> When PML is on, EPT A/D is enabled in the vmcs02 EPTP regardless of
> the vmcs12's EPTP value. The problem is that enabling A/D changes the
> behavior of L2's x86 page table walks as seen by L1. With A/D enabled,
> x86 page table walks are always treated as EPT writes. The EPT test in
> kvm-unit-tests's x86/vmx.c shows this failure.

Is PML required actually? Just eptad=1 I think (my machine doesn't have
PML but shows the bug).

Thanks for the review by the way. :)

Paolo