On 21/01/20 22:04, Sean Christopherson wrote: >> Alternatively, BUILD_BUG_ON((MMIO_SPTE_GEN_HIGH_MASK | >> MMIO_SPTE_GEN_LOW_MASK) & SPTE_(MMIO and/or SPECIAL)_MASK) > Or add both BUILD_BUG_ONs. In the end I decided to revert MMIO_SPTE_GEN_HIGH_START to PT64_SECOND_AVAIL_BITS_SHIFT (it makes sense since we use it for shadow_acc_track_saved_bits_shift, and whether to use shadow_acc_track_saved_bits_shift or MMIO_SPTE_GEN_HIGH_START depends on the SPTE_SPECIAL_MASK bits) and use Ben's suggested BUILD_BUG_ON. Paolo
