From 645386dfe6307dbb28f10a4513792a59beda0efa Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 4 Jan 2019 17:17:53 +0100 Subject: [PATCH] dma-mapping: don't BUG when calling dma_map_resource on RAM Use WARN_ON_ONCE to print a stack trace and return a proper error code instead. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy Tested-by: Marek Szyprowski --- include/linux/dma-mapping.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 9842085e6774..b904d55247ab 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -353,7 +353,8 @@ static inline dma_addr_t dma_map_resource(struct device *dev, BUG_ON(!valid_dma_direction(dir)); /* Don't allow RAM to be mapped */ - BUG_ON(pfn_valid(PHYS_PFN(phys_addr))); + if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr)))) + return DMA_MAPPING_ERROR; if (dma_is_direct(ops)) addr = dma_direct_map_resource(dev, phys_addr, size, dir, attrs);