On Mon, 21 Jan 2019, Davidlohr Bueso wrote: > ib_umem_get() uses gup_longterm() and relies on the lock to > stabilze the vma_list, so we cannot really get rid of mmap_sem > altogether, but now that the counter is atomic, we can get of > some complexity that mmap_sem brings with only pinned_vm. Reviewd-by: Christoph Lameter <cl@xxxxxxxxx>