Re: [PATCH v1 2/4] xen/pci: Introduce new CONFIG_HAS_PCI_ATS flag for PCI ATS functionality.

[Jan Beulich <jbeulich@xxxxxxxx>]

On 26.10.2020 18:17, Rahul Singh wrote:
> @@ -48,5 +50,27 @@ static inline int pci_ats_device(int seg, int bus, int 
> devfn)
>      return pci_find_ext_capability(seg, bus, devfn, PCI_EXT_CAP_ID_ATS);
>  }
>  
> +#else
> +
> +static inline int enable_ats_device(struct pci_dev *pdev,
> +                                    struct list_head *ats_list)
> +{
> +    return -ENODEV;

In addition to what Stefano has said, I don't think this is an
appropriate return value here either - -EOPNOTSUPP would seem
quite a bit closer to reality.

Jan