We do not support instantiating multiple IOMMUs. Before adding a virtio-iommu, check that no other IOMMU is present. This will detect both "iommu=smmuv3" machine parameter and another virtio-iommu instance.
Fixes: 70e89132c9 ("hw/arm/virt: Add the virtio-iommu device tree mappings") Reviewed-by: Eric Auger <eric.au...@redhat.com> Signed-off-by: Jean-Philippe Brucker <jean-phili...@linaro.org> --- hw/arm/virt.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/hw/arm/virt.c b/hw/arm/virt.c index f238766aa1..26069f943a 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -2471,6 +2471,11 @@ static void virt_machine_device_plug_cb(HotplugHandler *hotplug_dev, if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI)) { PCIDevice *pdev = PCI_DEVICE(dev); + if (vms->iommu != VIRT_IOMMU_NONE) { + error_setg(errp, "virt machine does not support multiple IOMMUs"); + return; + } + vms->iommu = VIRT_IOMMU_VIRTIO; vms->virtio_iommu_bdf = pci_get_bdf(pdev); create_virtio_iommu_dt_bindings(vms); -- 2.33.0