0

I have been working on trying to get SGX passthrough to VM using QEMU and Virsh (libvirt). Unfortunately, i cannot seem to passthrough SGX enclaves to my VMs. SGX (using DCAP) works on my host machine and i have tested with a client setup.

Just as note, my host machine is Ubuntu 24.04 LTS (Xeon Scalable Gen3 Intel CPU with support for SGX), and my virtual machine is running Ubuntu 24.04. My host is running these versions from stable releases

Compiled against library: libvirt 10.0.0
Using library: libvirt 10.0.0
Using API: QEMU 10.0.0
Running hypervisor: QEMU 8.2.2

Here is my full virtual-machine config

<domain type="kvm">
  <name>ubuntu24.04</name>
  <uuid>87cd126a-047f-4b41-938f-2d19ee19d198</uuid>
  <metadata>
    <libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0">
      <libosinfo:os id="http://ubuntu.com/ubuntu/24.04"/>
    </libosinfo:libosinfo>
  </metadata>
  <maxMemory slots="16" unit="KiB">82313216</maxMemory>
  <memory unit="KiB">65634304</memory>
  <currentMemory unit="KiB">65634304</currentMemory>
  <vcpu placement="static">10</vcpu>
  <os>
    <type arch="x86_64" machine="pc-q35-8.2">hvm</type>
    <boot dev="hd"/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <vmport state="off"/>
  </features>
  <cpu mode="host-passthrough" check="none" migratable="on">
    <feature policy="require" name="sgx"/>
    <feature policy="require" name="sgxlc"/>
    <feature policy="require" name="sgx1"/>
    <feature policy="require" name="sgx2"/>
    <feature policy="require" name="sgx-exinfo"/>
    <feature policy="require" name="sgx-debug"/>
    <feature policy="require" name="sgx-mode64"/>
    <feature policy="require" name="sgx-provisionkey"/>
    <feature policy="require" name="sgx-tokenkey"/>
    <feature policy="require" name="sgx-kss"/>
    <feature policy="require" name="sgx-edeccssa"/>
    <feature policy="require" name="sgx-aex-notify"/>
    <numa>
      <cell id="0" cpus="0-9" memory="65634304" unit="KiB"/>
    </numa>
  </cpu>
  <clock offset="utc">
    <timer name="rtc" tickpolicy="catchup"/>
    <timer name="pit" tickpolicy="delay"/>
    <timer name="hpet" present="no"/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>destroy</on_crash>
  <pm>
    <suspend-to-mem enabled="no"/>
    <suspend-to-disk enabled="no"/>
  </pm>
  <devices>
    <emulator>/usr/bin/qemu-system-x86_64</emulator>
    <disk type="file" device="disk">
      <driver name="qemu" type="qcow2" discard="unmap"/>
      <source file="/var/lib/libvirt/images/ubuntu24.04.qcow2"/>
      <target dev="vda" bus="virtio"/>
      <address type="pci" domain="0x0000" bus="0x04" slot="0x00" function="0x0"/>
    </disk>
    <disk type="file" device="cdrom">
      <driver name="qemu" type="raw"/>
      <target dev="sda" bus="sata"/>
      <readonly/>
      <address type="drive" controller="0" bus="0" target="0" unit="0"/>
    </disk>
    <controller type="usb" index="0" model="qemu-xhci" ports="15">
      <address type="pci" domain="0x0000" bus="0x02" slot="0x00" function="0x0"/>
    </controller>
    <controller type="pci" index="0" model="pcie-root"/>
    <controller type="pci" index="1" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="1" port="0x10"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x0" multifunction="on"/>
    </controller>
    <controller type="pci" index="2" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="2" port="0x11"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x1"/>
    </controller>
    <controller type="pci" index="3" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="3" port="0x12"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x2"/>
    </controller>
    <controller type="pci" index="4" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="4" port="0x13"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x3"/>
    </controller>
    <controller type="pci" index="5" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="5" port="0x14"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x4"/>
    </controller>
    <controller type="pci" index="6" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="6" port="0x15"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x5"/>
    </controller>
    <controller type="pci" index="7" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="7" port="0x16"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x6"/>
    </controller>
    <controller type="pci" index="8" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="8" port="0x17"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x7"/>
    </controller>
    <controller type="pci" index="9" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="9" port="0x18"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x03" function="0x0" multifunction="on"/>
    </controller>
    <controller type="pci" index="10" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="10" port="0x19"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x03" function="0x1"/>
    </controller>
    <controller type="pci" index="11" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="11" port="0x1a"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x03" function="0x2"/>
    </controller>
    <controller type="pci" index="12" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="12" port="0x1b"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x03" function="0x3"/>
    </controller>
    <controller type="pci" index="13" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="13" port="0x1c"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x03" function="0x4"/>
    </controller>
    <controller type="pci" index="14" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="14" port="0x1d"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x03" function="0x5"/>
    </controller>
    <controller type="sata" index="0">
      <address type="pci" domain="0x0000" bus="0x00" slot="0x1f" function="0x2"/>
    </controller>
    <controller type="virtio-serial" index="0">
      <address type="pci" domain="0x0000" bus="0x03" slot="0x00" function="0x0"/>
    </controller>
    <interface type="network">
      <mac address="52:54:00:1b:f4:13"/>
      <source network="default"/>
      <model type="virtio"/>
      <address type="pci" domain="0x0000" bus="0x01" slot="0x00" function="0x0"/>
    </interface>
    <serial type="pty">
      <target type="isa-serial" port="0">
        <model name="isa-serial"/>
      </target>
    </serial>
    <console type="pty">
      <target type="serial" port="0"/>
    </console>
    <channel type="unix">
      <target type="virtio" name="org.qemu.guest_agent.0"/>
      <address type="virtio-serial" controller="0" bus="0" port="1"/>
    </channel>
    <channel type="spicevmc">
      <target type="virtio" name="com.redhat.spice.0"/>
      <address type="virtio-serial" controller="0" bus="0" port="2"/>
    </channel>
    <input type="tablet" bus="usb">
      <address type="usb" bus="0" port="1"/>
    </input>
    <input type="mouse" bus="ps2"/>
    <input type="keyboard" bus="ps2"/>
    <graphics type="spice" autoport="yes">
      <listen type="address"/>
    </graphics>
    <sound model="ich9">
      <address type="pci" domain="0x0000" bus="0x00" slot="0x1b" function="0x0"/>
    </sound>
    <audio id="1" type="spice"/>
    <video>
      <model type="qxl" ram="65536" vram="65536" vgamem="16384" heads="1" primary="yes"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x01" function="0x0"/>
    </video>
    <redirdev bus="usb" type="spicevmc">
      <address type="usb" bus="0" port="2"/>
    </redirdev>
    <redirdev bus="usb" type="spicevmc">
      <address type="usb" bus="0" port="3"/>
    </redirdev>
    <watchdog model="itco" action="reset"/>
    <memballoon model="virtio">
      <address type="pci" domain="0x0000" bus="0x05" slot="0x00" function="0x0"/>
    </memballoon>
    <rng model="virtio">
      <backend model="random">/dev/urandom</backend>
      <address type="pci" domain="0x0000" bus="0x06" slot="0x00" function="0x0"/>
    </rng>
  </devices>
</domain>

A thing to note is that when i add EPC memory module inside the devices i get an error

<memory model='sgx-epc'>
    <target>
      <size unit='KiB'>16384</size>
    </target>
  </memory>

Error:

Error starting domain: internal error: QEMU unexpectedly closed the monitor (vm='ubuntu24.04'): 2025-02-21T17:27:05.276761Z qemu-system-x86_64: invalid object type: memory-backend-epc

Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/asyncjob.py", line 72, in cb_wrapper callback(asyncjob, args, kwargs) File "/usr/share/virt-manager/virtManager/asyncjob.py", line 108, in tmpcb callback(args, kwargs) File "/usr/share/virt-manager/virtManager/object/libvirtobject.py", line 57, in newfn ret = fn(self, *args, kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/share/virt-manager/virtManager/object/domain.py", line 1402, in startup self._backend.create() File "/usr/lib/python3/dist-packages/libvirt.py", line 1379, in create raise libvirtError('virDomainCreate() failed') libvirt.libvirtError: internal error: QEMU unexpectedly closed the monitor (vm='ubuntu24.04'): 2025-02-21T17:27:05.276761Z qemu-system-x86_64: invalid object type: memory-backend-epc

From the error, i am not to sure why it cannot find the module although its supported according to the official docs: https://libvirt.org/formatdomain.html#memory-devices

My Question:

  • Is my configuration correct?
  • Is there a certain config I need to enable to passthrough SGX.

I also already tested out answers from SGX Drivers are not showing with QEMU VM unfortunately they do not work, I am not sure if it's because of breaking changes with new versions.

Happy to get any ideas I can try to.

1 Answers1

0

After working on the configuration for a bit, i realized either this is a bug or a error in documentation. On bringing it the repo maintainer i created an issue and seems to be related with Apparmor on libvirt. https://gitlab.com/libvirt/libvirt/-/issues/751

Anyways still have to test if this fix will work. Waiting on how i can get access to my downstream Ubuntu system as i am on stable release.

Update 1: I have requested a bug report on ubuntu to backport the upstream to noble. https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/2100024

Update 2: PPA from this release fixes this problem https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/2100024 I successfully got SGX to work on VMs for our usecase. Will need to wait until it gets merged into stable.