On 11/23/21 18:00, Jason Gunthorpe wrote: > >> believe what you say and I trust your experience :) So could as well be >> that on such a "special" (or not so special) systems there should be a >> way to restrict it to privileged users only. > > At this point RDMA is about as "special" as people running large > ZONE_MOVABLE systems, and the two are going to start colliding > heavily. The RDMA VFIO migration driver should be merged soon which > makes VMs using this stuff finally practical. How does that work, I see the word migration, so does it cause pages to be migrated out of ZONE_MOVABLE before they are pinned? Similarly for io-uring we could be migrating pages to be pinned so that the end up consolidated close together, and prevent pathologic situations like in David's reproducer. IIRC that was a idea to do for long-term pins in general. > Jason >
