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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 On 3/24/26 04:48, Huang, Kai wrote: > >> /* >> - * Due to limited space in PTEs, the MMIO generation is a 19 bit subset of >> + * Due to limited space in PTEs, the MMIO generation is an 18 bit subset of >> * the memslots generation and is derived as follows: > > Is "a -> an" unintentional change? No, "a nineteen-bit" -> "an eighteen-bit". :) > Besides the changes to MMIO_GEN, the FROZEN_SPTE seems to have bit 10 set: > > #define FROZEN_SPTE (SHADOW_NONPRESENT_VALUE | 0x5a0ULL) > > When MBEC is enabled, IIUC such SPTE will be treated as present by hardware > if CPU supports execution-only SPTE. > > Also, when MBEC is enabled, per SDM if CPU doesn't support execution-only, > an SPTE with bit 0 clear but with bit 10 set will trigger EPT > miscofiguration, rather than EPT violation. > > So seems we should exclude bit 10 from FROZEN_SPTE. True, good catch (so 0x5a0 should become 0x1a0). Paolo