On Thu, Nov 22, 2018 at 09:55:25AM -0800, Linus Torvalds wrote: > No, the big immediate benefit of allowing "return -EINVAL" etc is > simply legibility and error avoidance. Well, I can tweak the last patch to return -EINVAL from dma_mapping_error instead of the old 1 is as bool true. The callers should all be fine, although I'd have to audit them. Still wouldn't help with being able to return different errors.