[PATCH] iommu/arm-smmu-v3: fix probe device bug due to duplicated stream IDS.

[Reaper Li]

From: Reaper <reaperlioc at glenfly.com>

Commit 9246b487ab3c ("PCI: Add function 0 DMA alias quirk for Glenfly Arise
chip ") add quirk to fix hda dma request issue, but IORT logic populaties
two identical IDs into the fwspec->ids array via DMA aliasing in
iort_pci_iommu_init() called by pci_for_each_dma_alias().

Signed-off-by: ReaperLi <reaperlioc at glenfly.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 2a8b46b94..996d3c0f8 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3476,10 +3476,21 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu,
 				rb_entry(existing, struct arm_smmu_stream, node)
 					->master;
 
+			struct device *mdev = master->dev;
+			struct device *existing_mdev = existing_master->dev;
+
 			/* Bridged PCI devices may end up with duplicated IDs */
 			if (existing_master == master)
 				continue;
 
+			/* Dma alias PCI devices may end up with duplicated IDs */
+			if (existing_mdev != mdev &&
+				dev_is_pci(existing_mdev) && dev_is_pci(mdev) &&
+				to_pci_dev(existing_mdev)->bus == to_pci_dev(mdev)->bus &&
+				pci_devs_are_dma_aliases(to_pci_dev(existing_mdev),
+										 to_pci_dev(mdev)))
+				continue;
+
 			dev_warn(master->dev,
 				 "Aliasing StreamID 0x%x (from %s) unsupported, expect DMA to be broken\n",
 				 sid, dev_name(existing_master->dev));
-- 
2.34.1