Only the first device that is passed when the domain is set up will have its reserved regions reserved in the iova address space. So if there are other devices in the group with unique reserved regions, those regions will not get reserved in the iova address space. All of the ranges do get set up in the iopagetables via calls to iommu_create_device_direct_mappings for all devices in a group.
In the case of vt-d system this resulted in messages like the following:
[ 1632.693264] DMAR: ERROR: DMA PTE for vPFN 0xf1f7e already set (to f1f7e003 not 173025001)
To make sure iova ranges are reserved for the reserved regions all of the devices, call iova_reserve_iommu_regions in iommu_dma_init_domain prior to exiting in the case where the domain is already initialized.
Cc: Robin Murphy robin.murphy@arm.com Cc: Joerg Roedel joro@8bytes.org Cc: Will Deacon will@kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 7c1b058c8b5a ("iommu/dma: Handle IOMMU API reserved regions") Signed-off-by: Jerry Snitselaar jsnitsel@redhat.com --- Robin: I wasn't positive if this is the correct solution, or if it should be done for the entire group at once.
drivers/iommu/dma-iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 2a9fa0c8cc00..5fd3cccbb233 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -707,7 +707,7 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, struct device *dev goto done_unlock; }
- ret = 0; + ret = iova_reserve_iommu_regions(dev, domain); goto done_unlock; }