On 10.02.2025 11:30, Mykyta Poturai wrote:
> From: Stewart Hildebrand <stewart.hildebr...@amd.com>
>
> Enable the use of IOMMU + PCI in dom0 without having to specify
> "pci-passthrough=yes".
Why? It _is_ passing through, even if Dom0 is special.
> @@ -83,9 +84,9 @@ static int __init pci_init(void)
> {
> /*
> * Enable PCI passthrough when has been enabled explicitly
> - * (pci-passthrough=on).
> + * (pci-passthrough=on) or IOMMU is present and enabled.
> */
> - if ( !pci_passthrough_enabled )
> + if ( !is_pci_passthrough_enabled() && !iommu_enabled )
> return 0;
I can't reasonably judge on this adjustment, but ...
> --- a/xen/drivers/pci/physdev.c
> +++ b/xen/drivers/pci/physdev.c
> @@ -19,7 +19,7 @@ ret_t pci_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void)
> arg)
> struct pci_dev_info pdev_info;
> nodeid_t node = NUMA_NO_NODE;
>
> - if ( !is_pci_passthrough_enabled() )
> + if ( !is_pci_passthrough_enabled() && !iommu_enabled )
> return -EOPNOTSUPP;
>
> ret = -EFAULT;
> @@ -57,7 +57,7 @@ ret_t pci_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void)
> arg)
> case PHYSDEVOP_pci_device_remove: {
> struct physdev_pci_device dev;
>
> - if ( !is_pci_passthrough_enabled() )
> + if ( !is_pci_passthrough_enabled() && !iommu_enabled )
> return -EOPNOTSUPP;
>
> ret = -EFAULT;
... these two certainly look wrong to be made. If an Arm-specific adjustment
is needed (and can be justified), a per-arch hook may need introducing.
Jan
