On a system with an Intel PCIe port configured as a nvme host device, iommu
initialization fails with
DMAR: Device scope type does not match for 0000:80:00.0
This is because the DMAR table reports this device as having scope 2
(ACPI_DMAR_SCOPE_TYPE_BRIDGE):
but the device has a type 0 PCI header:
80:00.0 Class 0600: Device 8086:2020 (rev 06)
00: 86 80 20 20 47 05 10 00 06 00 00 06 10 00 00 00
10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
20: 00 00 00 00 00 00 00 00 00 00 00 00 86 80 00 00
30: 00 00 00 00 90 00 00 00 00 00 00 00 00 01 00 00
VT-d works perfectly on this system, so there's no reason to bail out
on initialization due to this apparent scope mismatch. Add the class
0x06 ("PCI_BASE_CLASS_BRIDGE") as a heuristic for allowing DMAR
initialization for non-bridge PCI devices listed with scope bridge.
Signed-off-by: jimyan <jimyan@xxxxxxxxx>