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Subject: Re: [virtio-dev] Re: [PATCH 5/5] virtio: Add bounce DMA ops
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Srivatsa Vaddagiri <vatsa@codeaurora.org>,
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        will@kernel.org, linux-kernel@vger.kernel.org,
        pratikp@codeaurora.org
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From:   Jan Kiszka <jan.kiszka@siemens.com>
Message-ID: <303ace66-950c-955d-d750-74de5054788a@siemens.com>
Date:   Wed, 29 Apr 2020 12:55:56 +0200
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On 29.04.20 12:45, Michael S. Tsirkin wrote:
> On Wed, Apr 29, 2020 at 12:26:43PM +0200, Jan Kiszka wrote:
>> 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
> 
> Want to try implementing that?
> 

The desire is definitely there, currently "just" not the time.

Jan

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