From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srivatsa Vaddagiri Subject: Re: [RFC/PATCH 0/1] virtio_mmio: hypervisor specific interfaces for MMIO Date: Thu, 30 Apr 2020 15:59:39 +0530 Message-ID: <20200430102939.GG5097@quicinc.com> References: <1588240976-10213-1-git-send-email-vatsa@codeaurora.org> <20200430100821.GC19932@willie-the-truck> Reply-To: Srivatsa Vaddagiri Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Return-path: Content-Disposition: inline In-Reply-To: <20200430100821.GC19932@willie-the-truck> Sender: linux-kernel-owner@vger.kernel.org To: Will Deacon Cc: konrad.wilk@oracle.com, mst@redhat.com, jasowang@redhat.com, jan.kiszka@siemens.com, stefano.stabellini@xilinx.com, iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, virtio-dev@lists.oasis-open.org, tsoni@codeaurora.org, pratikp@codeaurora.org, christoffer.dall@arm.com, alex.bennee@linaro.org, linux-kernel@vger.kernel.org List-Id: virtualization@lists.linuxfoundation.org * Will Deacon [2020-04-30 11:08:22]: > > This patch is meant to seek comments. If its considered to be in right > > direction, will work on making it more complete and send the next version! > > What's stopping you from implementing the trapping support in the > hypervisor? Unlike the other patches you sent out, where the guest memory > is not accessible to the host, there doesn't seem to be any advantage to > not having trapping support, or am I missing something here? Hi Will, I have had this discussion with hypervisor folks. They seem to be concerned about complexity of having a VM's fault be handled in another untrusted VM. They are not keen to add MMIO support. -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation