VMD creates and assigns a separate IRQ domain when MSI-X remapping is enabled. For example VMD-MSI. But VMD doesn't assign IRQ domain when MSI-X remapping is disabled resulting child devices getting default PCI-MSI IRQ domain. Now when interrupt remapping is enabled by intel-iommu all the PCI devices are assigned INTEL-IR-MSI domain including VMD endpoints. But devices behind VMD get PCI-MSI IRQ domain when VMD create a root bus and configures child devices. As a result DMAR errors were observed when interrupt remapping was enabled on Intel Icelake CPUs. For instance: DMAR: DRHD: handling fault status reg 2 DMAR: [INTR-REMAP] Request device [0xe2:0x00.0] fault index 0xa00 [fault reason 0x25] Blocked a compatibility format interrupt request Signed-off-by: Nirmal Patel <nirmal.patel@xxxxxxxxxxxxxxx> --- drivers/pci/controller/vmd.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index eb05cceab964..5015adc04d19 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -853,6 +853,9 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features) vmd_attach_resources(vmd); if (vmd->irq_domain) dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain); + else + dev_set_msi_domain(&vmd->bus->dev, + dev_get_msi_domain(&vmd->dev->dev)); vmd_acpi_begin(); -- 2.26.2
