vtbar 4103 drivers/iommu/intel-iommu.c u32 vtbar; vtbar 4111 drivers/iommu/intel-iommu.c rc = pci_bus_read_config_dword(pdev->bus, PCI_DEVFN(0, 0), 0xb0, &vtbar); vtbar 4117 drivers/iommu/intel-iommu.c vtbar &= 0xffff0000; vtbar 4121 drivers/iommu/intel-iommu.c if (!drhd || drhd->reg_base_addr - vtbar != 0xa000) {