From b9bb694b9f62f4b31652223ed3ca38cf98bbb370 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Mon, 21 Sep 2020 16:08:01 +0100 Subject: iommu/io-pgtable-arm: Clean up faulty sanity check Checking for a nonzero dma_pfn_offset was a quick shortcut to validate whether the DMA == phys assumption could hold at all. Checking for a non-NULL dma_range_map is not quite equivalent, since a map may be present to describe a limited DMA window even without an offset, and thus this check can now yield false positives. However, it only ever served to short-circuit going all the way through to __arm_lpae_alloc_pages(), failing the canonical test there, and having a bit more to clean up. As such, we can simply remove it without loss of correctness. Reported-by: Naresh Kamboju Signed-off-by: Robin Murphy Signed-off-by: Christoph Hellwig --- drivers/iommu/io-pgtable-arm.c | 5 ----- 1 file changed, 5 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index d77e881516a4..f87cbb822a3d 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -751,11 +751,6 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg) if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS) return NULL; - if (!selftest_running && cfg->iommu_dev->dma_range_map) { - dev_err(cfg->iommu_dev, "Cannot accommodate DMA offset for IOMMU page tables\n"); - return NULL; - } - data = kmalloc(sizeof(*data), GFP_KERNEL); if (!data) return NULL; -- cgit v1.2.3