Date:   Fri, 10 Mar 2023 12:06:18 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Nicolin Chen <nicolinc@nvidia.com>
Cc:     Jean-Philippe Brucker <jean-philippe@linaro.org>,
        robin.murphy@arm.com, will@kernel.org, eric.auger@redhat.com,
        kevin.tian@intel.com, baolu.lu@linux.intel.com, joro@8bytes.org,
        shameerali.kolothum.thodi@huawei.com,
        linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev,
        linux-kernel@vger.kernel.org, yi.l.liu@intel.com
Subject: Re: [PATCH v1 02/14] iommufd: Add nesting related data structures
 for ARM SMMUv3
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On Thu, Mar 09, 2023 at 08:50:52PM -0800, Nicolin Chen wrote:
> On Thu, Mar 09, 2023 at 10:48:50AM -0400, Jason Gunthorpe wrote:
> 
> > Nicolin, I think we should tweak the uAPI here so that the
> > invalidation opaque data has a format tagged on its own, instead of
> > re-using the HWPT tag. Ie you can have a ARM SMMUv3 invalidate type
> > tag and also a virtio-viommu invalidate type tag.
> 
> The invalidation tage is shared with the hwpt allocation. Does
> it mean that virtio-iommu won't have it's own allocation tag?

We probably shouldn't assume it will

Jason