[ Sasha's backport helper bot ]
Hi,
The upstream commit SHA1 provided is correct: 229e6ee43d2a160a1592b83aad620d6027084aad
WARNING: Author mismatch between patch and upstream commit:
Backport author: Robin Murphy <robin.murphy@xxxxxxx>
Commit author: Pratyush Brahma <quic_pbrahma@xxxxxxxxxxx>
Status in newer kernel trees:
6.12.y | Present (different SHA1: 5018696b19bc)
6.6.y | Present (different SHA1: fe9d9839a755)
Note: The patch differs from the upstream commit:
---
1: 229e6ee43d2a1 ! 1: a937416dbd5d3 iommu/arm-smmu: Defer probe of clients after smmu device bound
@@ Metadata
## Commit message ##
iommu/arm-smmu: Defer probe of clients after smmu device bound
+ [ Upstream commit 229e6ee43d2a160a1592b83aad620d6027084aad ]
+
Null pointer dereference occurs due to a race between smmu
driver probe and client driver probe, when of_dma_configure()
for client is called after the iommu_device_register() for smmu driver
@@ Commit message
until the smmu device has bound to the arm smmu driver.
Fixes: 021bb8420d44 ("iommu/arm-smmu: Wire up generic configuration support")
- Cc: stable@xxxxxxxxxxxxxxx
+ Cc: stable@xxxxxxxxxxxxxxx # 6.6
Co-developed-by: Prakash Gupta <quic_guptap@xxxxxxxxxxx>
Signed-off-by: Prakash Gupta <quic_guptap@xxxxxxxxxxx>
Signed-off-by: Pratyush Brahma <quic_pbrahma@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20241004090428.2035-1-quic_pbrahma@xxxxxxxxxxx
[will: Add comment]
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
+ [rm: backport for context conflict prior to 6.8]
+ Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
## drivers/iommu/arm/arm-smmu/arm-smmu.c ##
@@ drivers/iommu/arm/arm-smmu/arm-smmu.c: static struct iommu_device *arm_smmu_probe_device(struct device *dev)
goto out_free;
- } else {
+ } else if (fwspec && fwspec->ops == &arm_smmu_ops) {
smmu = arm_smmu_get_by_fwnode(fwspec->iommu_fwnode);
+
+ /*
@@ drivers/iommu/arm/arm-smmu/arm-smmu.c: static struct iommu_device *arm_smmu_prob
+ if (!smmu)
+ return ERR_PTR(dev_err_probe(dev, -EPROBE_DEFER,
+ "smmu dev has not bound yet\n"));
+ } else {
+ return ERR_PTR(-ENODEV);
}
-
- ret = -EINVAL;
---
Results of testing on various branches:
| Branch | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.6.y | Success | Success |
