On 4/2/25 10:25, Andrea Righi via Devel wrote:
> = Overview =
>
> This patch set introduces support for acpi-generic-initiator devices,
> supported by QEMU [1].
>
> The acpi-generic-initiator object is required to support Multi-Instance GPU
> (MIG) configurations on NVIDIA GPUs [2]. MIG enables partitioning of GPU
> resources into multiple isolated instances, each requiring a dedicated NUMA
> node definition.
>
> = Implementation =
>
> This patch set implements the libvirt counterpart to the QEMU feature,
> enabling users to configure acpi-generic-initiator objects within libvirt
> domain XML.
>
> This includes:
> - adding XML syntax to define acpi-generic-initiator objects,
> - resolving the acpi-generic-initiator definitions into the proper QEMU
> command-line arguments,
> - ensuring compatibility with existing NUMA configuration.
>
> = Example =
>
> - Domain XML:
> ```
> ...
> <cpu mode='host-passthrough' check='none'>
> <numa>
> <cell id='0' cpus='0-15' memory='8388608' unit='KiB'/>
> <cell id='1' memory='0' unit='KiB'/>
> <cell id='2' memory='0' unit='KiB'/>
> <cell id='3' memory='0' unit='KiB'/>
> <cell id='4' memory='0' unit='KiB'/>
> <cell id='5' memory='0' unit='KiB'/>
> <cell id='6' memory='0' unit='KiB'/>
> <cell id='7' memory='0' unit='KiB'/>
> <cell id='8' memory='0' unit='KiB'/>
> </numa>
> </cpu>
> ...
> <devices>
> ...
> <hostdev mode='subsystem' type='pci' managed='no'>
> <source>
> <address domain='0x0009' bus='0x01' slot='0x00' function='0x0'/>
> </source>
> <address type='pci' domain='0x0000' bus='0x03' slot='0x00'
> function='0x0'/>
> </hostdev>
> <acpi-generic-initiator>
> <alias name="gi1"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>1</numa-node>
> </acpi-generic-initiator>
> <acpi-generic-initiator>
> <alias name="gi2"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>2</numa-node>
> </acpi-generic-initiator>
> <acpi-generic-initiator>
> <alias name="gi3"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>3</numa-node>
> </acpi-generic-initiator>
> <acpi-generic-initiator>
> <alias name="gi4"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>4</numa-node>
> </acpi-generic-initiator>
> <acpi-generic-initiator>
> <alias name="gi5"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>5</numa-node>
> </acpi-generic-initiator>
> <acpi-generic-initiator>
> <alias name="gi6"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>6</numa-node>
> </acpi-generic-initiator>
> <acpi-generic-initiator>
> <alias name="gi7"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>7</numa-node>
> </acpi-generic-initiator>
> <acpi-generic-initiator>
> <alias name="gi8"/>
> <pci-dev>hostdev0</pci-dev>
> <numa-node>8</numa-node>
> </acpi-generic-initiator>
> </devices>
> ```
>
> - Generated QEMU command line options:
> ```
> ... /usr/bin/qemu-system-aarch64 \
> ...
> -object
> '{"qom-type":"memory-backend-ram","id":"ram-node0","size":8589934592}' \
> -numa node,nodeid=0,cpus=0-15,memdev=ram-node0 \
> -numa node,nodeid=1 \
> -numa node,nodeid=2 \
> -numa node,nodeid=3 \
> -numa node,nodeid=4 \
> -numa node,nodeid=5 \
> -numa node,nodeid=6 \
> -numa node,nodeid=7 \
> -numa node,nodeid=8 \
> ...
> -device
> '{"driver":"vfio-pci","host":"0009:01:00.0","id":"hostdev0","bus":"pci.3","addr":"0x0"}'
> ...
> -object acpi-generic-initiator,id=gi1,pci-dev=hostdev0,node=1 \
> -object acpi-generic-initiator,id=gi2,pci-dev=hostdev0,node=2 \
> -object acpi-generic-initiator,id=gi3,pci-dev=hostdev0,node=3 \
> -object acpi-generic-initiator,id=gi4,pci-dev=hostdev0,node=4 \
> -object acpi-generic-initiator,id=gi5,pci-dev=hostdev0,node=5 \
> -object acpi-generic-initiator,id=gi6,pci-dev=hostdev0,node=6 \
> -object acpi-generic-initiator,id=gi7,pci-dev=hostdev0,node=7 \
> -object acpi-generic-initiator,id=gi8,pci-dev=hostdev0,node=8
> ```
>
> = References =
>
> [1] https://lore.kernel.org/all/20231225045603.7654-2-ank...@nvidia.com/
> [2] https://www.nvidia.com/en-in/technologies/multi-instance-gpu/
>
> ChangeLog v2 -> v3:
> - replaced <text/> with proper types in the XML schema
> - avoid mixing g_free() and VIR_FREE()
> - use virXMLPropString() instead of looping all XML nodes
> - report proper errors with virReportError()
> - use virBufferEscapeString() to process strings passed by the user
> - fix broken formatting of function headers
> - misc coding style fixes
>
> ChangeLog v1 -> v2:
> - split parser and driver changes in separate patches
> - introduce a new qemu capability flag
> - introduce test in qemuxmlconftest
>
> Andrea Righi (6):
> schema: Introduce acpi-generic-initiator definition
> conf: Introduce acpi-generic-initiator device
> qemu: Allow to define NUMA nodes without memory or CPUs assigned
> qemu: capabilies: Introduce QEMU_CAPS_ACPI_GENERIC_INITIATOR
> qemu: support acpi-generic-initiator
> qemu: Add test case for acpi-generic-initiator
>
> src/ch/ch_domain.c | 1 +
> src/conf/domain_conf.c | 159
> +++++++++++++++++++++
> src/conf/domain_conf.h | 14 ++
> src/conf/domain_postparse.c | 1 +
> src/conf/domain_validate.c | 37 +++++
> src/conf/numa_conf.c | 3 +
> src/conf/schemas/domaincommon.rng | 19 +++
> src/conf/virconftypes.h | 2 +
> src/libxl/libxl_driver.c | 6 +
> src/lxc/lxc_driver.c | 6 +
> src/qemu/qemu_capabilities.c | 2 +
> src/qemu/qemu_capabilities.h | 1 +
> src/qemu/qemu_command.c | 49 ++++++-
> src/qemu/qemu_domain.c | 2 +
> src/qemu/qemu_domain_address.c | 4 +
> src/qemu/qemu_driver.c | 3 +
> src/qemu/qemu_hotplug.c | 5 +
> src/qemu/qemu_postparse.c | 1 +
> src/qemu/qemu_validate.c | 1 +
> src/test/test_driver.c | 4 +
> .../caps_10.0.0_x86_64+amdsev.xml | 1 +
> tests/qemucapabilitiesdata/caps_10.0.0_x86_64.xml | 1 +
> tests/qemucapabilitiesdata/caps_9.0.0_x86_64.xml | 1 +
> tests/qemucapabilitiesdata/caps_9.1.0_riscv64.xml | 1 +
> tests/qemucapabilitiesdata/caps_9.1.0_x86_64.xml | 1 +
> .../caps_9.2.0_aarch64+hvf.xml | 1 +
> .../caps_9.2.0_x86_64+amdsev.xml | 1 +
> tests/qemucapabilitiesdata/caps_9.2.0_x86_64.xml | 1 +
> .../acpi-generic-initiator.x86_64-latest.args | 55 +++++++
> .../acpi-generic-initiator.x86_64-latest.xml | 102 +++++++++++++
> tests/qemuxmlconfdata/acpi-generic-initiator.xml | 102 +++++++++++++
> tests/qemuxmlconftest.c | 1 +
> 32 files changed, 581 insertions(+), 7 deletions(-)
> create mode 100644
> tests/qemuxmlconfdata/acpi-generic-initiator.x86_64-latest.args
> create mode 100644
> tests/qemuxmlconfdata/acpi-generic-initiator.x86_64-latest.xml
> create mode 100644 tests/qemuxmlconfdata/acpi-generic-initiator.xml
>
Sorry for late review. Normally, to make it up to you I'd fix all the
small nits and merge, but this is introducing new feature and yet not
updating documentation and that's a show stopper. Also, don't forget to
add a NEWS.rst entry ;-)
Michal
