On Tue, Jan 19, 2021 at 08:43:29PM -0500, Pavel Tatashin wrote: > +.. note:: > + Techniques that rely on long-term pinnings of memory (especially, RDMA and > + vfio) are fundamentally problematic with ZONE_MOVABLE and, therefore, memory > + hot remove. Pinned pages cannot reside on ZONE_MOVABLE, to guarantee that > + memory can still get hot removed - be aware that pinning can fail even if > + there is plenty of free memory in ZONE_MOVABLE. In addition, using > + ZONE_MOVABLE might make page pinning more expensive, because pages have to be > + migrated off that zone first. Just to point out, if anyone is using RDMA/etc with hotplug memory, this series is likekly going to be a major regression for those users. Jason
