Merge tag 'dma-mapping-4.13-3' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fix from Christoph Hellwig:
 "Another dma-mapping regression fix"

* tag 'dma-mapping-4.13-3' of git://git.infradead.org/users/hch/dma-mapping:
  of: fix DMA mask generation

drivers/of/device.c

@@ -89,6 +89,7 @@ int of_dma_configure(struct device *dev, struct device_node *np)
 	bool coherent;
 	unsigned long offset;
 	const struct iommu_ops *iommu;
+	u64 mask;
 
 	/*
 	 * Set default coherent_dma_mask to 32 bit.  Drivers are expected to
@@ -134,10 +135,9 @@ int of_dma_configure(struct device *dev, struct device_node *np)
 	 * Limit coherent and dma mask based on size and default mask
 	 * set by the driver.
 	 */
-	dev->coherent_dma_mask = min(dev->coherent_dma_mask,
-				     DMA_BIT_MASK(ilog2(dma_addr + size)));
-	*dev->dma_mask = min((*dev->dma_mask),
-			     DMA_BIT_MASK(ilog2(dma_addr + size)));
+	mask = DMA_BIT_MASK(ilog2(dma_addr + size - 1) + 1);
+	dev->coherent_dma_mask &= mask;
+	*dev->dma_mask &= mask;
 
 	coherent = of_dma_is_coherent(np);
 	dev_dbg(dev, "device is%sdma coherent\n",