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

[Ani Sinha]

> On 27-Jun-2023, at 2:32 PM, Igor Mammedov <imammedo@redhat.com> wrote:
> 
> 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?

If ARI breaks this, it will break other areas in QEMU too, ex anywhere 
pci_get_function_0() is used.
Regardless, I think at least the tests are worth fixing, particularly the mess 
with hd-geo-test.

> 
>> 
>> 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;
>