On 2021-07-16 12:33 a.m., Christoph Hellwig wrote: > On Thu, Jul 15, 2021 at 10:45:44AM -0600, Logan Gunthorpe wrote: >> @@ -194,6 +194,8 @@ static int __dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, >> else >> ents = ops->map_sg(dev, sg, nents, dir, attrs); >> >> + WARN_ON_ONCE(ents == 0); > > Turns this into a negative error code while we're at it, just to keep > the callers sane? > Sure thing. All the feedback makes sense, we'll fix it up and send a v2 in due course. Thanks, Logan