Re: [RFC 06/20] iommu: Add iommu_device_init[exit]_user_dma interfaces

From: Jason Gunthorpe
Date: Mon Sep 27 2021 - 10:39:56 EST


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