From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-dev-return-7202-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 6AC8F985E7F for ; Wed, 29 Apr 2020 09:52:13 +0000 (UTC) Date: Wed, 29 Apr 2020 05:52:05 -0400 From: "Michael S. Tsirkin" Message-ID: <20200429055125-mutt-send-email-mst@kernel.org> References: <1588073958-1793-1-git-send-email-vatsa@codeaurora.org> <1588073958-1793-6-git-send-email-vatsa@codeaurora.org> <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> MIME-Version: 1.0 In-Reply-To: <20200429094410.GD5097@quicinc.com> Subject: [virtio-dev] Re: [PATCH 5/5] virtio: Add bounce DMA ops Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Content-Disposition: inline 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 List-ID: On Wed, Apr 29, 2020 at 03:14:10PM +0530, Srivatsa Vaddagiri wrote: > * Michael S. Tsirkin [2020-04-29 02:50:41]: >=20 > > So it seems that with modern Linux, all one needs > > to do on x86 is mark the device as untrusted. > > It's already possible to do this with ACPI and with OF - would that be > > sufficient for achieving what this patchset is trying to do? >=20 > In my case, its not sufficient to just mark virtio device untrusted and t= hus > activate the use of swiotlb. All of the secondary VM memory, including th= ose > allocate by swiotlb driver, is private to it. So why not make the bounce buffer memory shared then? > An additional piece of memory is > available to secondary VM which is shared between VMs and which is where = I need > swiotlb driver to do its work. >=20 > --=20 > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member > of Code Aurora Forum, hosted by The Linux Foundation --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org