On Wed, Jul 12, 2023 at 10:32:13AM +0800, Baolu Lu wrote: > > btw is there value of moving the group handling logic from > > iommu_queue_iopf() to this common function? > > > > I wonder whether there is any correctness issue if not forwarding > > partial request to iommufd. If not this can also help reduce > > notifications to the user until the group is ready. > > I don't think there's any correctness issue. But it should be better if > we can inject the page faults to vm guests as soon as possible. There's > no requirement to put page requests to vIOMMU's hardware page request > queue at the granularity of a fault group. Thoughts? Not sure I understand you correctly, but we can't inject partial fault groups: if the HW PRI queue overflows, the last fault in a group may be lost, so the non-last faults in that group already injected won't be completed (until PRGI reuse), leaking PRI request credits and guest resources. Thanks, Jean
