Re: [PATCH 1/4] IOMMU/x86: switch to alternatives-call patching in further instances

[Andrew Cooper <amc96@xxxxxxxx>]

On 01/12/2021 09:39, Jan Beulich wrote:
> --- a/xen/drivers/passthrough/pci.c
> +++ b/xen/drivers/passthrough/pci.c
> @@ -1457,24 +1462,24 @@ static int iommu_get_device_group(
>      if ( !is_iommu_enabled(d) || !ops->get_device_group_id )
>          return 0;
>  
> -    group_id = ops->get_device_group_id(seg, bus, devfn);
> +    group_id = iommu_call(ops, get_device_group_id, seg, bus, devfn);

So I was going to suggest adjusting this to use more pci_sbdf_t, but the
Intel implementation can fail and return -1.

However, given the observations in patch 4, I'd instead recommend
dropping all of this.

Everything unrelated to get_device_group() looks fine.

~Andrew