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Date:   Wed, 29 Apr 2020 06:45:10 -0400
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Jan Kiszka <jan.kiszka@siemens.com>
Cc:     Srivatsa Vaddagiri <vatsa@codeaurora.org>,
        Lu Baolu <baolu.lu@linux.intel.com>, tsoni@codeaurora.org,
        virtio-dev@lists.oasis-open.org, konrad.wilk@oracle.com,
        jasowang@redhat.com, christoffer.dall@arm.com,
        virtualization@lists.linux-foundation.org, alex.bennee@linaro.org,
        iommu@lists.linux-foundation.org, stefano.stabellini@xilinx.com,
        will@kernel.org, linux-kernel@vger.kernel.org,
        pratikp@codeaurora.org
Subject: Re: [PATCH 5/5] virtio: Add bounce DMA ops
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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?

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