diff options
| -rw-r--r-- | drivers/pci/intel-iommu.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index 4eaec2fa1369..dcf051d53b74 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -2316,8 +2316,19 @@ static int iommu_should_identity_map(struct pci_dev *pdev, int startup) * Assume that they will -- if they turn out not to be, then we can * take them out of the 1:1 domain later. */ - if (!startup) - return pdev->dma_mask > DMA_BIT_MASK(32); + if (!startup) { + /* + * If the device's dma_mask is less than the system's memory + * size then this is not a candidate for identity mapping. + */ + u64 dma_mask = pdev->dma_mask; + + if (pdev->dev.coherent_dma_mask && + pdev->dev.coherent_dma_mask < dma_mask) + dma_mask = pdev->dev.coherent_dma_mask; + + return dma_mask >= dma_get_required_mask(&pdev->dev); + } return 1; } |