Re: [PATCH 08/16] KVM: x86/mmu: Bug the VM if kvm_zap_gfn_range() is called for TDX

From: Edgecombe, Rick P
Date: Thu May 16 2024 - 17:46:37 EST


On Tue, 2024-05-14 at 17:59 -0700, Rick Edgecombe wrote:
>
> For lack of a better method currently, use kvm_gfn_shared_mask() to
> determine if private memory cannot be zapped (as in TDX, the only VM type
> that sets it).

Trying to replace kvm_gfn_shared_mask() with something appropriate, I saw that
SNP actually uses this function:
https://lore.kernel.org/kvm/20240501085210.2213060-12-michael.roth@xxxxxxx/

So trying to have a helper that says "The VM can't zap and refault in memory at
will" won't cut it. I guess there would have to be some more specific. I'm
thinking to just drop this patch instead.