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Date:   Fri, 15 Apr 2022 23:07:00 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Stefano Stabellini <sstabellini@kernel.org>
Cc:     Oleksandr Tyshchenko <olekstysh@gmail.com>,
        xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Juergen Gross <jgross@suse.com>, Julien Grall <julien@xen.org>
Subject: Re: [RFC PATCH 6/6] arm/xen: Assign xen-virtio DMA ops for virtio
 devices in Xen guests
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On Fri, Apr 15, 2022 at 03:02:45PM -0700, Stefano Stabellini wrote:
> This makes sense overall. Considering that the swiotlb-xen case and the
> virtio case are mutually exclusive, I would write it like this:

Curious question:  Why can't the same grant scheme also be used for
non-virtio devices?  I really hate having virtio hooks in the arch
dma code.  Why can't Xen just say in DT/ACPI that grants can be used
for a given device?