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Date:   Mon, 27 Sep 2021 11:39:47 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     "Tian, Kevin" <kevin.tian@intel.com>
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Subject: Re: [RFC 06/20] iommu: Add iommu_device_init[exit]_user_dma
 interfaces
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On Mon, Sep 27, 2021 at 01:32:34PM +0000, Tian, Kevin wrote:

> but I'm little worried that even vfio-pci itself cannot be bound now,
> which implies that all devices in a group which are intended to be
> used by the user must be bound to vfio-pci in a breath before the 
> user attempts to open any of them, i.e. late-binding and device-
> hotplug is disallowed after the initial open. I'm not sure how 
> important such an usage would be, but it does cause user-tangible
> semantics change.

Oh, that's bad..

I guess your approach is the only way forward, it will have to be
extensively justified in the commit message for Greg et al.

Jason