Re: [PATCH kernel v4 02/11] vfio/spapr: Relax the IOMMU compatibility check

From: Alex Williamson
Date: Fri Apr 29 2016 - 11:41:58 EST


On Fri, 29 Apr 2016 18:55:15 +1000
Alexey Kardashevskiy <aik@xxxxxxxxx> wrote:

> We are going to have multiple different types of PHB on the same system
> with POWER8 + NVLink and PHBs will have different IOMMU ops. However
> we only really care about one callback - create_table - so we can
> relax the compatibility check here.
>
> Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx>
> Reviewed-by: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
> ---
> drivers/vfio/vfio_iommu_spapr_tce.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
> index 0582b72..3054e3f 100644
> --- a/drivers/vfio/vfio_iommu_spapr_tce.c
> +++ b/drivers/vfio/vfio_iommu_spapr_tce.c
> @@ -1188,7 +1188,8 @@ static int tce_iommu_attach_group(void *iommu_data,
> goto unlock_exit;
> }
> table_group_tmp = iommu_group_get_iommudata(tcegrp->grp);
> - if (table_group_tmp->ops != table_group->ops) {
> + if (table_group_tmp->ops->create_table !=
> + table_group->ops->create_table) {
> pr_warn("tce_vfio: Group %d is incompatible with group %d\n",
> iommu_group_id(iommu_group),
> iommu_group_id(tcegrp->grp));

Acked-by: Alex Williamson <alex.williamson@xxxxxxxxxx>