On 5/11/2022 2:10 AM, Lorenzo Pieralisi wrote: > [Adding Marc, to keep an eye on IRQ domain usage] > > On Mon, May 02, 2022 at 01:48:59AM -0700, Nirmal Patel wrote: >> 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. > I would encourage you to rewrite this log, it is unclear - granted, > I don't know intel-iommu internals - but IMHO if you explain the > issue and the fix thoroughly this could avoid repeating what > you have to do in patch(2). > > Please describe how VMD handles IRQ domains and how you are fixing > that. > > Thanks, > Lorenzo I will add more information to the commit logs. Thanks, nirmal >> 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 >>
