mirror of https://github.com/xemu-project/xemu.git
26863366b2
In DMAR table, the drhd is set to cover all PCI devices when intel_iommu
is on. To support bypass iommu feature, we need to walk the PCI bus with
bypass_iommu disabled and add explicit scope data in DMAR drhd structure.
/mnt/sdb/wxg/qemu-next/qemu/build/x86_64-softmmu/qemu-system-x86_64 \
-machine q35,accel=kvm,default_bus_bypass_iommu=true \
-cpu host \
-m 16G \
-smp 36,sockets=2,cores=18,threads=1 \
-device pxb-pcie,bus_nr=0x10,id=pci.10,bus=pcie.0,addr=0x3 \
-device pxb-pcie,bus_nr=0x20,id=pci.20,bus=pcie.0,addr=0x4,bypass_iommu=true \
-device pcie-root-port,port=0x1,chassis=1,id=pci.11,bus=pci.10,addr=0x0 \
-device pcie-root-port,port=0x2,chassis=2,id=pci.21,bus=pci.20,addr=0x0 \
-device virtio-scsi-pci,id=scsi0,bus=pci.11,addr=0x0 \
-device virtio-scsi-pci,id=scsi1,bus=pci.21,addr=0x0 \
-drive file=/mnt/sdb/wxg/fedora-48g.qcow2,format=qcow2,if=none,id=drive-scsi0-0-0-0,cache=none,aio=native \
-device scsi-hd,bus=scsi1.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,bootindex=1 \
-device intel-iommu \
-nographic \
And we get the guest configuration:
~ lspci -vt
-+-[0000:20]---00.0-[21]----00.0 Red Hat, Inc. Virtio SCSI
+-[0000:10]---00.0-[11]----00.0 Red Hat, Inc. Virtio SCSI
\-[0000:00]-+-00.0 Intel Corporation 82G33/G31/P35/P31 Express DRAM Controller
+-01.0 Device 1234:1111
+-02.0 Intel Corporation 82574L Gigabit Network Connection
+-03.0 Red Hat, Inc. QEMU PCIe Expander bridge
+-04.0 Red Hat, Inc. QEMU PCIe Expander bridge
+-1f.0 Intel Corporation 82801IB (ICH9) LPC Interface Controller
+-1f.2 Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 6 port SATA Controller [AHCI mode]
\-1f.3 Intel Corporation 82801I (ICH9 Family) SMBus Controller
With bypass_iommu enabled on root bus, the attached devices will bypass iommu:
/sys/class/iommu/dmar0
├── devices
│ ├── 0000:10:00.0 -> ../../../../pci0000:10/0000:10:00.0
│ └── 0000:11:00.0 -> ../../../../pci0000:10/0000:10:00.0/0000:11:00.0
Signed-off-by: Xingang Wang <wangxingang5@huawei.com>
Message-Id: <1625748919-52456-8-git-send-email-wangxingang5@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
|
||
|---|---|---|
| .. | ||
| kvm | ||
| xen | ||
| Kconfig | ||
| acpi-build.c | ||
| acpi-build.h | ||
| acpi-common.c | ||
| acpi-common.h | ||
| acpi-microvm.c | ||
| acpi-microvm.h | ||
| amd_iommu.c | ||
| amd_iommu.h | ||
| e820_memory_layout.c | ||
| e820_memory_layout.h | ||
| fw_cfg.c | ||
| fw_cfg.h | ||
| generic_event_device_x86.c | ||
| intel_iommu.c | ||
| intel_iommu_internal.h | ||
| kvmvapic.c | ||
| meson.build | ||
| microvm.c | ||
| multiboot.c | ||
| multiboot.h | ||
| pc.c | ||
| pc_piix.c | ||
| pc_q35.c | ||
| pc_sysfw.c | ||
| pc_sysfw_ovmf-stubs.c | ||
| pc_sysfw_ovmf.c | ||
| port92.c | ||
| trace-events | ||
| trace.h | ||
| vmmouse.c | ||
| vmport.c | ||
| x86-iommu-stub.c | ||
| x86-iommu.c | ||
| x86.c | ||