On Vi, 2017-06-23 at 14:31 +0800, Herbert Xu wrote: > > The crypto API cannot rely on users providing aligned buffers. So > if your driver has an alignment requirement, it either has to use > the existing crypto API alignmask setting which can cope with some > unaligned inputs, e.g., the IV if you use the skcipher walk > mechanism, > or you must copy unaligned data yourself before performing DMA on > them. > > Cheers, Normally I would agree with you, if it's a weird requirement coming from hardware or driver. In this case I think it's different. This is not a limitation coming from one driver or one particular hardware variety. It applies to all platforms that do not have hw cache coherence and a large enough cacheline. A couple of lines below the allocation hash is linked into a scatterlist, a data structure with remarkably high chances of ending up in a DMA endpoint, yet we choose to ignore all other DMA requirements? Cheers, Radu.
