What is "DMAR: PTE Read access is not set"?

[Mark Hills]

Recently, seeing from the kernel when my audio device (Layla3G, PCI) is 
open:

  [ 2333.598177] DMAR: [DMA Read NO_PASID] Request device [0a:00.0] fault addr 0xfffe0000 [fault reason 0x06] PTE Read access is not set
  [ 2333.768836] DMAR: DRHD: handling fault status reg 3
  [ 2338.376854] dmar_fault: 80 callbacks suppressed

I'm not really sure where to begin here; does it mean that snd-echo3g 
should be making some up-front declaration of how it uses some DMA area?

Seems to have appeared in the 5.14.x series (currently 5.14.16) but also I 
did a BIOS update in that time for another issue. 5.15.6 (latest stable) 
is also still affected.

Audio plays fine; but my logs are full of these excess messages.

-- 
Mark