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Subject: Re: [PATCH 5/5] virtio: Add bounce DMA ops
To:     "Michael S. Tsirkin" <mst@redhat.com>,
        Srivatsa Vaddagiri <vatsa@codeaurora.org>
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        pratikp@codeaurora.org
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From:   Jan Kiszka <jan.kiszka@siemens.com>
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Date:   Wed, 29 Apr 2020 12:26:43 +0200
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On 29.04.20 12:20, Michael S. Tsirkin wrote:
> On Wed, Apr 29, 2020 at 03:39:53PM +0530, Srivatsa Vaddagiri wrote:
>> That would still not work I think where swiotlb is used for pass-thr devices
>> (when private memory is fine) as well as virtio devices (when shared memory is
>> required).
> 
> So that is a separate question. When there are multiple untrusted
> devices, at the moment it looks like a single bounce buffer is used.
> 
> Which to me seems like a security problem, I think we should protect
> untrusted devices from each other.
> 

Definitely. That's the model we have for ivshmem-virtio as well.

Jan

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