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Date:   Fri, 8 Sep 2023 01:50:36 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Alex Williamson <alex.williamson@redhat.com>
Cc:     Jason Gunthorpe <jgg@nvidia.com>, ankita@nvidia.com,
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        danw@nvidia.com, anuaggarwal@nvidia.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH v8 1/1] vfio/nvgpu: Add vfio pci variant module for grace
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On Thu, Sep 07, 2023 at 10:04:10PM -0600, Alex Williamson wrote:
> > I think it really depends on what the qemu side wants to do..
> 
> Ok, I thought you had been one of the proponents of the fake BAR
> approach as more resembling CXL.  Do we need to reevaluate that the
> tinkering with the VM machine topology and firmware tables would better
> align to a device specific region that QEMU inserts into the VM address
> space so that bare metal and virtual machine versions of this device
> look more similar?  Thanks,

Yes, providing something to a VM that doesn't look anything like the
underlying hardware feels pretty strange.