On Thu, May 13, 2021 at 04:31:47PM -0600, Logan Gunthorpe wrote: > Attempt to find the mapping type for P2PDMA pages on the first > DMA map attempt if it has not been done ahead of time. > > Previously, the mapping type was expected to be calculated ahead of > time, but if pages are to come from userspace then there's no > way to ensure the path was checked ahead of time. > > With this change it's no longer invalid to call pci_p2pdma_map_sg() > before the mapping type is calculated so drop the WARN_ON when that > is the case. Why?
