From: Joerg Roedel jroedel@suse.de
[ Upstream commit 7cad554887f1c5fd77e57e6bf4be38370c2160cb ]
Do not force devices supporting IOMMUv2 to be direct mapped when memory encryption is active. This might cause them to be unusable because their DMA mask does not include the encryption bit.
Signed-off-by: Joerg Roedel jroedel@suse.de Link: https://lore.kernel.org/r/20200824105415.21000-2-joro@8bytes.org Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/amd/iommu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 200ee948f6ec1..37c74c842f3a3 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -2650,7 +2650,12 @@ static int amd_iommu_def_domain_type(struct device *dev) if (!dev_data) return 0;
- if (dev_data->iommu_v2) + /* + * Do not identity map IOMMUv2 capable devices when memory encryption is + * active, because some of those devices (AMD GPUs) don't have the + * encryption bit in their DMA-mask and require remapping. + */ + if (!mem_encrypt_active() && dev_data->iommu_v2) return IOMMU_DOMAIN_IDENTITY;
return 0;