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[109.66.7.121]) by smtp.gmail.com with ESMTPSA id t67sm7743622wmg.40.2020.04.29.03.20.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Apr 2020 03:20:50 -0700 (PDT) Date: Wed, 29 Apr 2020 06:20:48 -0400 From: "Michael S. Tsirkin" To: Srivatsa Vaddagiri Cc: Lu Baolu , tsoni@codeaurora.org, virtio-dev@lists.oasis-open.org, konrad.wilk@oracle.com, jan.kiszka@siemens.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 Message-ID: <20200429061621-mutt-send-email-mst@kernel.org> References: <20200428121232-mutt-send-email-mst@kernel.org> <20200428174952.GA5097@quicinc.com> <20200428163448-mutt-send-email-mst@kernel.org> <275eba4b-dd35-aa95-b2e3-9c5cbf7c6d71@linux.intel.com> <20200429004531-mutt-send-email-mst@kernel.org> <20200429023842-mutt-send-email-mst@kernel.org> <20200429094410.GD5097@quicinc.com> <20200429055125-mutt-send-email-mst@kernel.org> <20200429100953.GE5097@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200429100953.GE5097@quicinc.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. > -- > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member > of Code Aurora Forum, hosted by The Linux Foundation