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On host (UEFI legacy mode):

lkd> !pfn 0xf0
    PFN 000000F0 at address FFFFFA8000002D00
    flink       FFFFFFFFFFFFFFFF  blink / share count FFFFFFFFFFFFFFFF  pteaddress FFFFFFFFFFFFFFFF
    reference count FFFF    used entry count  FFFF      NotMapped color 3F   Priority 7
    restore pte FFFFFFFFFFFFFFFF  containing page        FFFFFFFFFFFFF  Trans      MPRWEXY
    Modified Shared ReadInProgress WriteInProgress InPageError ParityError RemovalRequested

On VM (legacy BIOS):

kd> !pfn 0xf0
    PFN 000000F0 at address FFFFFA8000002D00
    flink       00000000  blink / share count 00000000  pteaddress 00000000
    reference count 0000    used entry count  0000      NonCached color 0   Priority 0
    restore pte 00000000  containing page        000000  Zeroed                            

For the record !db 0xf0000 works correctly on both machines, and the PFN entry is the same before and after the momentary mapping performed by !db on both machines. Could the first one be a stupid kd -kl / livekd issue again?

Curious. I thought it could be that 0xf0 has never been mapped as opposed to mapped then unmapped, and for some reason left as MiNonCached and not MiNotMapped (and it may or may not return it to MiNotMapped when unmapping a cached area, but I don't know). I would have thought that this range would never have been mapped on ntoskrnl because it's not supposed to be using BIOS services.

On the host:

lkd> !pfn 0xf1
    PFN 000000F1 at address FFFFFA8000002D30
    flink       FFFFFFFFFFFFFFFF  blink / share count FFFFFFFFFFFFFFFF  pteaddress B47756FFFFE9FFFF
    reference count 517C    used entry count  B4E9      Cached    color 2D   Priority 7
    restore pte FFFFFFFFFFFFFFFF  containing page        756FFFFE9FFFF  Bad           WEXY
          WriteInProgress InPageError ParityError RemovalRequested

This time it's 'Cached', and clearly contains garbage, so the MiNotMapped part of the question may be irrelevant, and should have perhaps been whats the difference between a garbage PFN entry and a zero intialised one?

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