Messages in this thread | | | Subject | Re: [PATCH v5 03/15] KVM: SVM: Disable SEV/SEV-ES if NPT is disabled | From | Paolo Bonzini <> | Date | Thu, 22 Apr 2021 19:08:05 +0200 |
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On 22/04/21 18:15, Sean Christopherson wrote: >> Support for 5-level page tables on NPT is not hard to fix and could be >> tested by patching QEMU. However, the !NPT case would also have to be fixed >> by extending the PDP and PML4 stacking trick to a PML5. > > Isn't that backwards? It's the nested NPT case that requires the stacking trick. > When !NPT is disabled in L0 KVM, 32-bit guests are run with PAE paging. Maybe > I'm misunderstanding what you're suggesting.
Yes, you're right. NPT is easy but we would have to guess what the spec would say about MAXPHYADDR, while nNPT would require the stacking of a PML5. Either way, blocking KVM is the easiest thing todo.
Paolo
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