I have pushed this series On Thu, May 15, 2025 at 07:48:07AM -0700, Matthew R. Ochs wrote:
This patch series adds support for configuring the PCI high memory MMIO window size for aarch64 virt machine types using the highmem-mmio-size feature introduced in QEMU v10.0.0 [1]. It allows users to configure the size of the high memory MMIO window above 4GB, which can be required to support PCI passthrough with devices that have a large BARs.
The feature is exposed through the existing pcihole64 element associated with the PCIe root controller:
<controller type='pci' index='0' model='pcie-root'> <pcihole64 unit='GiB'>512</pcihole64> </controller>
This existing schema supports the same semantics for the QEMU PC machine pci-hole64-size parameter and is a natural fit for supporting the highmem-mmio-size feature on the aarch64 virt machine.
This series is applied over master and depends on the recently merged patch [2] that added support for QEMU v10.0.0 aarch64 capabilities.
For your convenience, this series is also available on Github [3].
[1] https://github.com/qemu/qemu/commit/f10104aeae3a17f181d5bb37b7fd7dad7fe86cba [2] https://github.com/nvmochs/libvirt/commit/cea2ee1d28780808172911e5c586478d4e... [3] git fetch https://github.com/nvmochs/libvirt.git pci_highmem_mmio_size_pcihole64
Signed-off-by: Matthew R. Ochs <mochs@nvidia.com>
Changelog: v3 - Patch 2 updates: + Use positive check in qemuBuildGlobalControllerCommandLine + Only allow pcihole64 for PCIe root controllers with arm virt - Added review tags from Daniel P. Berrangé for patch 1 and 3 v2 - Use existing XML scmhema (pcihole64 element) instead of a new one
Matthew R. Ochs (3): qemu: Add capability for PCI high memory MMIO size qemu: Add command line support for PCI high memory MMIO size tests: Add pcihole64 test for virt machine
src/qemu/qemu_capabilities.c | 2 ++ src/qemu/qemu_capabilities.h | 1 + src/qemu/qemu_command.c | 14 ++++++++- src/qemu/qemu_validate.c | 4 ++- .../caps_10.0.0_aarch64.xml | 1 + .../pcihole64-virt.aarch64-latest.args | 31 +++++++++++++++++++ .../pcihole64-virt.aarch64-latest.xml | 29 +++++++++++++++++ tests/qemuxmlconfdata/pcihole64-virt.xml | 17 ++++++++++ tests/qemuxmlconftest.c | 1 + 9 files changed, 98 insertions(+), 2 deletions(-) create mode 100644 tests/qemuxmlconfdata/pcihole64-virt.aarch64-latest.args create mode 100644 tests/qemuxmlconfdata/pcihole64-virt.aarch64-latest.xml create mode 100644 tests/qemuxmlconfdata/pcihole64-virt.xml
-- 2.46.0
With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|