Re: [PATCH] KVM: mmu: Fix SPTE encoding of MMIO generation upper half

[Paolo Bonzini]

On 08/12/20 22:12, Sean Christopherson wrote:
> > #define MMIO_SPTE_GEN_MASK               GENMASK_ULL(MMIO_SPTE_GEN_LOW_BITS + MMIO_SPTE_GEN_HIGH_BITS - 1, 0)
> What if we leave MMIO_SPTE_GEN_MASK as is, GENMASK_ULL(17, 0), and instead add a
> BUILD_BUG_ON() to assert that it matches the above logic?  It's really easy to
> get lost when reading through the chain of defines, I find the explicit mask
> helps provide an anchor/reference for understand what's going on.  It'll require
> an update if/when PT64_SECOND_AVAIL_BITS_SHIFT, but that's not necessarily a bad
> thing, e.g. the comment above this block will also be stale.

Sounds good.

Paolo