Re: [PATCH v2] kconfig: Add PCIe devices to s390x machines

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 4/7/23 14:01, Cédric Le Goater wrote:
> It is useful to extend the number of available PCI devices to KVM guests
> for passthrough scenarios and also to expose these models to a different
> (big endian) architecture. Include models for Intel Ethernet adapters
> and one USB controller, which all support MSI-X. Devices only supporting
> INTx won't work on s390x.
> 
> Signed-off-by: Cédric Le Goater <clg@redhat.com>
> ---
> 
>   Tested under KVM as a machine device, under KVM nested as a passthrough
>   device
> 
>   hw/s390x/Kconfig | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/hw/s390x/Kconfig b/hw/s390x/Kconfig
> index 5e7d8a2bae8b..7a82c58cdf6e 100644
> --- a/hw/s390x/Kconfig
> +++ b/hw/s390x/Kconfig
> @@ -10,3 +10,7 @@ config S390_CCW_VIRTIO
>       select SCLPCONSOLE
>       select VIRTIO_CCW
>       select MSI_NONBROKEN
> +    imply PCI_EXPRESS

No, PCIe is a bus, which is implemented in s390-pci-bus.c;
S390_CCW_VIRTIO exposes this bus, so we Kconfig SELECT it.

> +    imply E1000E_PCI_EXPRESS
> +    imply IGB_PCI_EXPRESS
> +    imply USB_XHCI_PCI

These are devices you can plug on a PCIe bus, so Kconfig
IMPLY is correct.