NVMe: Use dma_set_mask() correctly
In some circumstances setting a 64-bit DMA mask can fail, as explained
in Documentation/DMA-API-HOWTO.txt. Use the recommended code sequence
to set a 32-bit DMA mask if setting a 64-bit DMA mask fails.
Reported-by: Chayan Biswas <Chayan.Biswas@sandisk.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 8493708..a57d3bc 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1927,8 +1927,14 @@
INIT_LIST_HEAD(&dev->namespaces);
dev->pci_dev = pdev;
pci_set_drvdata(pdev, dev);
- dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
- dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
+
+ if (!dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)))
+ dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
+ else if (!dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)))
+ dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+ else
+ goto disable;
+
result = nvme_set_instance(dev);
if (result)
goto disable;