Re: [PATCH v2 2/2] intel_iommu: Make PASID-cache and PIOTLB type invalid in legacy mode

[CLEMENT MATHIEU--DRIF]

Reviewed-by: Clément Mathieu--Drif<clement.mathieu--drif@eviden.com>

Super reactive!

Maybe we can continue along this path after the handlers are implemented.
It would be great to make sure we don't process PASID related descriptors when 
not in scalable mode.
What are your thoughts?

Thanks
>cmd



On 13/08/2024 09:44, Zhenzhong Duan wrote:
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>
> In vtd_process_inv_desc(), VTD_INV_DESC_PC and VTD_INV_DESC_PIOTLB are
> bypassed without scalable mode check. These two types are not valid
> in legacy mode and we should report error.
>
> Suggested-by: Yi Liu <yi.l.liu@intel.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> ---
>   hw/i386/intel_iommu.c | 22 +++++++++++-----------
>   1 file changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> index 68cb72a481..90cd4e5044 100644
> --- a/hw/i386/intel_iommu.c
> +++ b/hw/i386/intel_iommu.c
> @@ -2763,17 +2763,6 @@ static bool vtd_process_inv_desc(IntelIOMMUState *s)
>           }
>           break;
>
> -    /*
> -     * TODO: the entity of below two cases will be implemented in future 
> series.
> -     * To make guest (which integrates scalable mode support patch set in
> -     * iommu driver) work, just return true is enough so far.
> -     */
> -    case VTD_INV_DESC_PC:
> -        break;
> -
> -    case VTD_INV_DESC_PIOTLB:
> -        break;
> -
>       case VTD_INV_DESC_WAIT:
>           trace_vtd_inv_desc("wait", inv_desc.hi, inv_desc.lo);
>           if (!vtd_process_wait_desc(s, &inv_desc)) {
> @@ -2795,6 +2784,17 @@ static bool vtd_process_inv_desc(IntelIOMMUState *s)
>           }
>           break;
>
> +    /*
> +     * TODO: the entity of below two cases will be implemented in future 
> series.
> +     * To make guest (which integrates scalable mode support patch set in
> +     * iommu driver) work, just return true is enough so far.
> +     */
> +    case VTD_INV_DESC_PC:
> +    case VTD_INV_DESC_PIOTLB:
> +        if (s->scalable_mode) {
> +            break;
> +        }
> +    /* fallthrough */
>       default:
>           error_report_once("%s: invalid inv desc: hi=%"PRIx64", lo=%"PRIx64
>                             " (unknown type)", __func__, inv_desc.hi,
> --
> 2.34.1
>
>