Re: [PATCH v12 01/13] vfio: VFIO_IOMMU_SET_PASID_TABLE

Auger Eric
2021-04-11T12:13:38Z

Hi Zenghui,

On 4/7/21 11:33 AM, Zenghui Yu wrote:
> Hi Eric,
>
> On 2021/2/24 5:06, Eric Auger wrote:
>> +/*
>> + * VFIO_IOMMU_SET_PASID_TABLE - _IOWR(VFIO_TYPE, VFIO_BASE + 18,
>> + *            struct vfio_iommu_type1_set_pasid_table)
>> + *
>> + * The SET operation passes a PASID table to the host while the
>> + * UNSET operation detaches the one currently programmed. Setting
>> + * a table while another is already programmed replaces the old table.
>
> It looks to me that this description doesn't match the IOMMU part.

Yep that's misleanding.

I replaced it by:

It is allowed to "SET" the table several times without un-setting as
long as the table config does not stay IOMMU_PASID_CONFIG_TRANSLATE.

>
> [v14,05/13] iommu/smmuv3: Implement attach/detach_pasid_table
>
> |    case IOMMU_PASID_CONFIG_TRANSLATE:
> |        /* we do not support S1 <-> S1 transitions */
> |        if (smmu_domain->s1_cfg.set)
> |            goto out;
>
> Maybe I've misread something?
>
>
> Thanks,
> Zenghui
>

Thanks

Eric