If a device requires an identity map then it is not safe to attach a
domain that can remap addresses. Warn the user if this occurs.

Signed-off-by: James Sewart <[email protected]>
---
 drivers/iommu/intel-iommu.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 2e00e8708f06..104d36f225a7 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5101,6 +5101,11 @@ static int intel_iommu_attach_device(struct iommu_domain 
*domain,
                }
        }
 
+       if (iommu_no_mapping(dev)) {
+               dmar_domain = si_domain;
+               dev_warn(dev, "VT-d: Device is required to use identity IOMMU 
mapping, ignoring domain attached\n");
+       }
+
        iommu = device_to_iommu(dev, &bus, &devfn);
        if (!iommu)
                return -ENODEV;
-- 
2.17.1

_______________________________________________
iommu mailing list
[email protected]
https://lists.linuxfoundation.org/mailman/listinfo/iommu

Reply via email to