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Date:   Wed, 29 Apr 2020 15:30:03 -0700
From:   Jacob Pan <jacob.jun.pan@linux.intel.com>
To:     Auger Eric <eric.auger@redhat.com>
Cc:     "Tian, Kevin" <kevin.tian@intel.com>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Joerg Roedel <joro@8bytes.org>,
        David Woodhouse <dwmw2@infradead.org>,
        Jean-Philippe Brucker <jean-philippe@linaro.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        "Raj, Ashok" <ashok.raj@intel.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        Christoph Hellwig <hch@infradead.org>,
        Jonathan Cameron <jic23@kernel.org>,
        jacob.jun.pan@linux.intel.com
Subject: Re: [PATCH v12 4/8] iommu/vt-d: Add bind guest PASID support
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On Wed, 29 Apr 2020 16:12:01 +0200
Auger Eric <eric.auger@redhat.com> wrote:

> >> in last review Eric raised the open about what about binding the
> >> same PASID to the same pdev multiple times. We discussed that
> >> should be disallowed. Here can you check whether aux_domain is
> >> enabled on pdev to restrict multiple-binding only for
> >> sub-devices?  
> > Why aux_domain is sufficient? A pdev could have aux_domain enabled
> > but still bind pdev many times more than its mdevs.
> > 
> > Either we allow multiple bind or not.  
> 
> I tried to figure out whether binding the same PASID to the same pdev
> was meaningful. I understood it is not. If this case can be detected
> at VFIO level I am fine as well.
I will remove the multiple bind support for now. Reintroduce it when we
enable mdev.

Thanks,

Jacob