Until all upstream devices have their DMA ops swizzled to point at the SMMU, we need to treat the IOMMU_DOMAIN_DMA domain as bypass to avoid putting devices into an empty address space when detaching from VFIO.
Signed-off-by: Will Deacon <[email protected]> --- drivers/iommu/arm-smmu-v3.c | 7 ++++++- drivers/iommu/arm-smmu.c | 7 +++++++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index d96d45ddf500..4ff73ff64e49 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1687,7 +1687,12 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) goto out_unlock; smmu_group->domain = smmu_domain; - smmu_group->ste.bypass = false; + + /* + * FIXME: This should always be "false" once we have IOMMU-backed + * DMA ops for all devices behind the SMMU. + */ + smmu_group->ste.bypass = domain->type == IOMMU_DOMAIN_DMA; ret = arm_smmu_install_ste_for_group(smmu_group); if (IS_ERR_VALUE(ret)) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index f21332a15040..2409e3bd3df2 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1094,6 +1094,13 @@ static int arm_smmu_domain_add_master(struct arm_smmu_domain *smmu_domain, if (ret) return ret == -EEXIST ? 0 : ret; + /* + * FIXME: This won't be needed once we have IOMMU-backed DMA ops + * for all devices behind the SMMU. + */ + if (smmu_domain->domain.type == IOMMU_DOMAIN_DMA) + return 0; + for (i = 0; i < cfg->num_streamids; ++i) { u32 idx, s2cr; -- 2.1.4 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
