From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH v6 0/7] Add virtio-iommu driver Date: Fri, 11 Jan 2019 13:28:46 +0100 Message-ID: <20190111122846.GE5825@8bytes.org> References: <20181211182104.18241-1-jean-philippe.brucker@arm.com> <20181212103545.GV16835@8bytes.org> <9110873f-d344-b6b9-c722-9accfc329db2@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <9110873f-d344-b6b9-c722-9accfc329db2@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Jean-Philippe Brucker Cc: "virtio-dev@lists.oasis-open.org" , "kevin.tian@intel.com" , Lorenzo Pieralisi , "tnowicki@caviumnetworks.com" , "mst@redhat.com" , Marc Zyngier , "linux-pci@vger.kernel.org" , "jasowang@redhat.com" , Will Deacon , Robin Murphy , "virtualization@lists.linux-foundation.org" , "iommu@lists.linux-foundation.org" , "robh+dt@kernel.org" , "bhelgaas@google.com" , "frowand.list@gmail.com" , "kvmarm@lists.cs.columbia.edu" , "devicetree@vger.kernel.org" List-Id: devicetree@vger.kernel.org Hi Jean-Philippe, On Thu, Dec 13, 2018 at 12:50:29PM +0000, Jean-Philippe Brucker wrote: > We already do deferred flush: UNMAP requests are added to the queue by > iommu_unmap(), and then flushed out by iotlb_sync(). So we switch to the > host only on iotlb_sync(), or when the request queue is full. So the mappings can stay in place until iotlb_sync() returns? What happens when the guest sends a map-request for a region it sent and unmap request before, but did not call iotlb_sync inbetween? Regards, Joerg