From 205e1b7f51e4af2643eb1d61a6503e415cd1e014 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 22 Dec 2017 14:50:47 +0100 Subject: [PATCH] dma-mapping: warn when there is no coherent_dma_mask These days all devices should have a DMA coherent mask, and most dma_ops implementations rely on that fact. But just to be sure add an assert to ring the warning bell if that is not the case. Signed-off-by: Christoph Hellwig Reviewed-by: Vladimir Murzin Reviewed-by: Konrad Rzeszutek Wilk --- include/linux/dma-mapping.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index d84951865be7..16add66d5b68 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -513,6 +513,7 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size, void *cpu_addr; BUG_ON(!ops); + WARN_ON_ONCE(dev && !dev->coherent_dma_mask); if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr)) return cpu_addr;