I'm trying to get Qubes-OS 4 (running with kernel-latest-4.18.7-3) to run on the NUC8i7HVK.
One of the last BIOS updates broke the ACPI DMAR table.
From /var/log/xen/console/hypervisor.log (with iommu=verbose):
(XEN) [VT-D]Host address width 39
(XEN) [VT-D]found ACPI_DMAR_DRHD:
(XEN) [VT-D] dmaru->address = fed90000
(XEN) [VT-D]drhd->address = fed90000 iommu->reg = ffff82c0021b2000
(XEN) [VT-D]cap = 1c0000c40660462 ecap = 19e2ff0505e
(XEN) [VT-D] endpoint: 0000:00:02.0
(XEN) [VT-D]found ACPI_DMAR_DRHD:
(XEN) [VT-D] dmaru->address = fed91000
(XEN) [VT-D]drhd->address = fed91000 iommu->reg = ffff82c0021b4000
(XEN) [VT-D]cap = d2008c40660462 ecap = f050da
(XEN) [VT-D] IOAPIC: 0000:f0:1f.0
(XEN) [VT-D] MSI HPET: 0000:00:1f.0
(XEN) [VT-D]Unknown scope type 0x5
(XEN) [VT-D]Unknown scope type 0x5
(XEN) [VT-D]Unknown scope type 0x5
(XEN) [VT-D] flags: INCLUDE_ALL
(XEN) [VT-D]found ACPI_DMAR_RMRR:
(XEN) [VT-D] endpoint: 0000:00:14.0
(XEN) [VT-D] RMRR region: base_addr 6f703000 end_address 6f94cfff
(XEN) [VT-D]found ACPI_DMAR_RMRR:
(XEN) [VT-D]Overlapping RMRRs [6f703000,6f94cfff] and [6f703000,6f94cfff]
(XEN) Failed to parse ACPI DMAR. Disabling VT-d.
A previous BIOS (don't know the exact version) did work:
(XEN) Intel VT-d iommu 0 supported page sizes: 4kB, 2MB, 1GB.
(XEN) Intel VT-d iommu 1 supported page sizes: 4kB, 2MB, 1GB.
(XEN) Intel VT-d Snoop Control not enabled.
(XEN) Intel VT-d Dom0 DMA Passthrough not enabled.
(XEN) Intel VT-d Queued Invalidation enabled.
(XEN) Intel VT-d Interrupt Remapping enabled.
(XEN) Intel VT-d Posted Interrupt not enabled.
(XEN) Intel VT-d Shared EPT tables enabled.
(XEN) I/O virtualisation enabled
(XEN) - Dom0 mode: Relaxed
(XEN) Interrupt remapping enabled
(XEN) nr_sockets: 1
(XEN) Enabled directed EOI with ioapic_ack_old on!
(XEN) ENABLING IO-APIC IRQs