On Tue, Oct 9, 2018 at 8:02 AM Benjamin Herrenschmidt <b...@kernel.crashing.org> wrote: > > On Wed, 2018-10-03 at 16:10 -0700, Alexander Duyck wrote: > > > - * Because 32-bit DMA masks are so common we expect every > > > architecture > > > - * to be able to satisfy them - either by not supporting more > > > physical > > > - * memory, or by providing a ZONE_DMA32. If neither is the case, > > > the > > > - * architecture needs to use an IOMMU instead of the direct > > > mapping. > > > - */ > > > - if (mask < phys_to_dma(dev, DMA_BIT_MASK(32))) > > > + u64 min_mask; > > > + > > > + if (IS_ENABLED(CONFIG_ZONE_DMA)) > > > + min_mask = DMA_BIT_MASK(ARCH_ZONE_DMA_BITS); > > > + else > > > + min_mask = DMA_BIT_MASK(32); > > > + > > > + min_mask = min_t(u64, min_mask, (max_pfn - 1) << PAGE_SHIFT); > > > + > > > + if (mask >= phys_to_dma(dev, min_mask)) > > > return 0; > > > -#endif > > > return 1; > > > } > > > > So I believe I have run into the same issue that Guenter reported. On > > an x86_64 system w/ Intel IOMMU. I wasn't able to complete boot and > > all probe attempts for various devices were failing with -EIO errors. > > > > I believe the last mask check should be "if (mask < phys_to_dma(dev, > > min_mask))" not a ">=" check. > > Right, that test is backwards. I needed to change it here too (powermac > with the rest of the powerpc series). > > Cheers, > Ben. > >
Hi, I'm working on a MIPS64 soc with PCIe root complex on it, and it appears that this series of patches are causing all PCI drivers that request 64bit mask to fail with -5. It's broken in 4.19. However, I just checked, it working on master. We may need to backport a couple of patches to 4.19. I'm not sure though which patches should be backported as there were at least 10 patches resolving this dma_direct area recently. Christoph, Robin. Can we ask Greg to backport all these changes ? What do you think ? Thanks, Ramon. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu