On Tue, 8 Sep 2020 at 16:56, Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> wrote: > > > On 08/09/2020 16:44, Logan Gunthorpe wrote: > > On 2020-09-08 9:28 a.m., Tvrtko Ursulin wrote: > >>> > >>> 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)) > >> > >> I'd extend the condition to be, just to be safe: > >> if (dma && sgl && !sg_dma_len(s.sgp)) > >> > > > > Right, good catch, that's definitely necessary. > > > >>> + 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)); > >>> + } > >> > >> Otherwise has this been tested or alternatively how to test it? (How to > >> repro the issue.) > > > > It has not been tested. To test it, you need Tom's patch set without the > > last "DO NOT MERGE" patch: > > > > https://lkml.kernel.org/lkml/20200907070035.GA25114@xxxxxxxxxxxxx/T/ > > Tom, do you have a branch somewhere I could pull from? (Just being lazy > about downloading a bunch of messages from the archives.) I don't unfortunately. I'm working locally with poor internet. > > What GPU is in your Lenovo x1 carbon 5th generation and what > graphical/desktop setup I need to repro? Is this enough info?: $ lspci -vnn | grep VGA -A 12 00:02.0 VGA compatible controller [0300]: Intel Corporation HD Graphics 620 [8086:5916] (rev 02) (prog-if 00 [VGA controller]) Subsystem: Lenovo ThinkPad X1 Carbon 5th Gen [17aa:224f] Flags: bus master, fast devsel, latency 0, IRQ 148 Memory at eb000000 (64-bit, non-prefetchable) [size=16M] Memory at 60000000 (64-bit, prefetchable) [size=256M] I/O ports at e000 [size=64] [virtual] Expansion ROM at 000c0000 [disabled] [size=128K] Capabilities: [40] Vendor Specific Information: Len=0c <?> Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00 Capabilities: [ac] MSI: Enable+ Count=1/1 Maskable- 64bit- Capabilities: [d0] Power Management version 2 Capabilities: [100] Process Address Space ID (PASID) Capabilities: [200] Address Translation Service (ATS) > > Regards, > > Tvrtko _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization