On Thu, 27 Aug 2020 at 22:36, Logan Gunthorpe <logang@xxxxxxxxxxxx> wrote: > > > > On 2020-08-23 6:04 p.m., Tom Murphy wrote: > > I have added a check for the sg_dma_len == 0 : > > """ > > } __sgt_iter(struct scatterlist *sgl, bool dma) { > > struct sgt_iter s = { .sgp = sgl }; > > > > + if (sgl && sg_dma_len(sgl) == 0) > > + s.sgp = NULL; > > > > if (s.sgp) { > > ..... > > """ > > at location [1]. > > but it doens't fix the problem. > > Based on my read of the code, it looks like we also need to change usage > of sgl->length... Something like the rough patch below, maybe? > > Also, Tom, do you have an updated version of the patchset to convert the > Intel IOMMU to dma-iommu available? The last one I've found doesn't > apply cleanly (I'm assuming parts of it have been merged in slightly > modified forms). > I'll try and post one in the next 24hours > Thanks, > > Logan > > -- > > diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h > b/drivers/gpu/drm/i915/i915 > index b7b59328cb76..9367ac801f0c 100644 > --- a/drivers/gpu/drm/i915/i915_scatterlist.h > +++ b/drivers/gpu/drm/i915/i915_scatterlist.h > @@ -27,13 +27,19 @@ static __always_inline struct sgt_iter { > } __sgt_iter(struct scatterlist *sgl, bool dma) { > struct sgt_iter s = { .sgp = sgl }; > > + if (sgl && !sg_dma_len(s.sgp)) > + s.sgp = NULL; > + > if (s.sgp) { > s.max = s.curr = s.sgp->offset; > - s.max += s.sgp->length; > - if (dma) > + > + if (dma) { > + s.max += sg_dma_len(s.sgp); > s.dma = sg_dma_address(s.sgp); > - else > + } else { > + s.max += s.sgp->length; > s.pfn = page_to_pfn(sg_page(s.sgp)); > + } > } > > return s; _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx