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Date:   Thu, 11 Feb 2021 08:44:26 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Alex Williamson <alex.williamson@redhat.com>
Cc:     Jason Gunthorpe <jgg@nvidia.com>,
        Max Gurtovoy <mgurtovoy@nvidia.com>,
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        kwankhede@nvidia.com, ACurrid@nvidia.com, gmataev@nvidia.com,
        cjia@nvidia.com, yishaih@nvidia.com, aik@ozlabs.ru
Subject: Re: [PATCH 8/9] vfio/pci: use x86 naming instead of igd
Message-ID: <20210211084426.GB2378134@infradead.org>
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On Tue, Feb 02, 2021 at 04:59:23PM -0700, Alex Williamson wrote:
> vfio-pci-igd support knows very little about the device, we're
> effectively just exposing a firmware table and some of the host bridge
> config space (read-only).  So the idea that the host kernel needs to
> have updated i915 support in order to expose the device to userspace
> with these extra regions is a bit silly.

On the other hand assuming the IGD scheme works for every device
with an Intel Vendor ID and a VGA classcode that hangs off an Intel
host bridge seems highly dangerous.  Is this actually going to work
for the new discreete Intel graphics?  For the old i740?  And if not
what is the failure scenario?