On 01/10/20 01:20, Eric van Tassell wrote: >> >> +int is_shadow_present_pte(u64 pte) >> { >> return (pte != 0) && !is_mmio_spte(pte); > From <Figure 28-1: Formats of EPTP and EPT Paging-Structure Entries" of > the manual I don't have at my fingertips right now, I believe you should > only check the low 3 bits(mask = 0x7). Since the upper bits are ignored, > might that not mean they're not guaranteed to be 0? No, this a property of the KVM MMU (and how it builds its PTEs) rather than the hardware present check. Paolo