Re: [PATCH v3 5/7] iommu/arm-smmu-v3: Populate smmu_domain->invs when attaching masters

Nicolin Chen
2025-10-17T21:12:05Z

On Sat, Oct 18, 2025 at 12:03:27AM +0800, kernel test robot wrote:
> sparse warnings: (new ones prefixed by >>)
> >> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:3208:33: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct arm_smmu_invs **invs_ptr @@ got struct arm_smmu_invs [noderef] __rcu ** @@
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:3208:33: sparse: expected struct arm_smmu_invs **invs_ptr
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:3208:33: sparse: got struct arm_smmu_invs [noderef] __rcu **
...
> > 3208 invst->invs_ptr = &new_smmu_domain->invs;
...
> > 3247 rcu_assign_pointer(*invst->invs_ptr, invst->new_invs);

Looks like we need:

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 8906c1625f428..398d8beb8f862 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -1105,7 +1105,7 @@ static inline bool arm_smmu_master_canwbs(struct arm_smmu_master *master)
* to_unref argument to an arm_smmu_invs_unref() call
*/
struct arm_smmu_inv_state {
- struct arm_smmu_invs **invs_ptr;
+ struct arm_smmu_invs __rcu **invs_ptr;
struct arm_smmu_invs *old_invs;
struct arm_smmu_invs *new_invs;
};

Will fix in v4.

Thanks
Nicolin