> On 11. Jan 2026, at 20:53, Shameer Kolothum <[email protected]> wrote:
>
> Set the MSI doorbell GPA property for accelerated SMMUv3 devices for use
> by KVM MSI setup. Also, since any meaningful use of vfio-pci devices with
> an accelerated SMMUv3 requires both KVM and a kernel irqchip, ensure
> those are specified when accel=on is selected.
>
> Reviewed-by: Nicolin Chen <[email protected]>
> Signed-off-by: Shameer Kolothum <[email protected]>
> ---
> hw/arm/virt.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 9d0568a7d5..08feadf0a8 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -3052,6 +3052,26 @@ static void
> virt_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
> /* The new SMMUv3 device is specific to the PCI bus */
> object_property_set_bool(OBJECT(dev), "smmu_per_bus", true, NULL);
> }
> + if (object_property_find(OBJECT(dev), "accel") &&
> + object_property_get_bool(OBJECT(dev), "accel", &error_abort)) {
> + hwaddr db_start;
> +
> + if (!kvm_enabled() || !kvm_irqchip_in_kernel()) {
> + error_setg(errp, "SMMUv3 accel=on requires KVM with "
> + "kernel-irqchip=on support");
> + return;
> + }
> +
> + if (vms->msi_controller == VIRT_MSI_CTRL_ITS) {
> + /* GITS_TRANSLATER page + offset */
> + db_start = base_memmap[VIRT_GIC_ITS].base + 0x10000 + 0x40;
> + } else {
> + /* MSI_SETSPI_NS page + offset */
> + db_start = base_memmap[VIRT_GIC_V2M].base + 0x40;
> + }
Hello,
Currently (but soon no longer the case for virt-11.0+), its=off means no MSI
controller at all instead of
GICv3 + GICv2m.
Would an else if with an error returned if no MSI controller is enabled be
adequate?
> + object_property_set_uint(OBJECT(dev), "msi-gpa", db_start,
> + &error_abort);
> + }
> }
> }
>
> --
> 2.43.0
>
>
