diff mbox series

[v2,5/8] hw/arm/virt: Reject instantiation of multiple IOMMUs

Message ID 20210903143208.2434284-6-jean-philippe@linaro.org
State Superseded
Headers show
Series virtio-iommu: Add ACPI support | expand

Commit Message

Jean-Philippe Brucker Sept. 3, 2021, 2:32 p.m. UTC 
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.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>

---
 hw/arm/virt.c | 5 +++++
 1 file changed, 5 insertions(+)

-- 
2.33.0

Comments

Eric Auger Sept. 6, 2021, 2:28 p.m. UTC | #1 
Hi Jean,
On 9/3/21 4:32 PM, Jean-Philippe Brucker wrote:
> 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.

>

> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>


You may add
Fixes: 70e89132c9 ("hw/arm/virt: Add the virtio-iommu device tree mappings")
as the problem already exists with dt.

Reviewed-by: Eric Auger <eric.auger@redhat.com>


Thanks

Eric
> ---

>  hw/arm/virt.c | 5 +++++

>  1 file changed, 5 insertions(+)

>

> diff --git a/hw/arm/virt.c b/hw/arm/virt.c

> index b4598d3fe6..5ca225291f 100644

> --- a/hw/arm/virt.c

> +++ b/hw/arm/virt.c

> @@ -2475,6 +2475,11 @@ 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);
diff mbox series

Patch

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index b4598d3fe6..5ca225291f 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -2475,6 +2475,11 @@  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);