We shouldn't dereference "iommu" until after we have checked that it is non-NULL. Fixes: f08978b0fdbf ("sparc64: Enable sun4v dma ops to use IOMMU v2 APIs") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> --- Applies to sparc.git diff --git a/arch/sparc/kernel/pci_sun4v.c b/arch/sparc/kernel/pci_sun4v.c index 06981cc7..cabb609 100644 --- a/arch/sparc/kernel/pci_sun4v.c +++ b/arch/sparc/kernel/pci_sun4v.c @@ -478,11 +478,10 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist, BUG_ON(direction == DMA_NONE); iommu = dev->archdata.iommu; - atu = iommu->atu; - if (nelems == 0 || !iommu) return 0; - + atu = iommu->atu; + prot = HV_PCI_MAP_ATTR_READ; if (direction != DMA_TO_DEVICE) prot |= HV_PCI_MAP_ATTR_WRITE; -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html