On Wed, Jan 29, 2020 at 06:07:14PM +0100, Christian Borntraeger wrote: > > DMA can be done to NORMAL memory as well. > > Exactly. > I think iucv uses GFP_DMA because z/VM needs those buffers to reside below 2GB (which is ZONA_DMA for s390). The normal way to allocate memory with addressing limits would be to use dma_alloc_coherent and friends. Any chance to switch iucv over to that? Or is there no device associated with it?
