Re: [RESEND PATCH v5 5/5] hw/pci: ensure PCIE devices are plugged into only slot 0 of PCIE port

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 26 Jun 2023 21:42:44 +0530
Ani Sinha <anisinha@redhat.com> wrote:

> PCI Express ports only have one slot, so PCI Express devices can only be
> plugged into slot 0 on a PCIE port. Enforce it.

btw, previously you mentioned ARI.
So if we turn it on, wouldn't this patch actually become regression?

> 
> CC: jusual@redhat.com
> CC: imammedo@redhat.com
> Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2128929
> Signed-off-by: Ani Sinha <anisinha@redhat.com>
> Reviewed-by: Julia Suvorova <jusual@redhat.com>
> ---
>  hw/pci/pci.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index bf38905b7d..426af133b0 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -64,6 +64,7 @@ bool pci_available = true;
>  static char *pcibus_get_dev_path(DeviceState *dev);
>  static char *pcibus_get_fw_dev_path(DeviceState *dev);
>  static void pcibus_reset(BusState *qbus);
> +static bool pcie_has_upstream_port(PCIDevice *dev);
>  
>  static Property pci_props[] = {
>      DEFINE_PROP_PCI_DEVFN("addr", PCIDevice, devfn, -1),
> @@ -1189,6 +1190,11 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev,
>                     name);
>  
>         return NULL;
> +    } else if (pcie_has_upstream_port(pci_dev) && PCI_SLOT(devfn)) {
> +        error_setg(errp, "PCI: slot %d is not valid for %s,"
> +                   " parent device only allows plugging into slot 0.",
> +                   PCI_SLOT(devfn), name);
> +        return NULL;
>      }
>  
>      pci_dev->devfn = devfn;