From: Geert Uytterhoeven > Sent: 13 May 2020 10:49 ... > > I don't want to apply this to older kernels as it could cause extra > > memory usage for no good reason. I have no idea why a non ARC system > > would want it :( > > I think the reference to ARC is a red herring. > The real issue is that buffers used for DMA may not have the required > alignment, which is not limited to ARC systems. > > Note that I'm also not super happy with the extra memory usage. > But devm_*() conveniences come with their penalties... Interesting thought. Could the devm 'header' be put right at the end of the kmalloc() buffer? Then the driver would be given aligned address. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)