[PATCH v3 3/7] iommu/arm-smmu-v3: Introduce a per-domain arm_smmu_invs array

[Nicolin Chen]

On Mon, Oct 20, 2025 at 09:10:56AM -0300, Jason Gunthorpe wrote:
> On Fri, Oct 17, 2025 at 01:12:02PM -0700, Nicolin Chen wrote:
> > On Fri, Oct 17, 2025 at 09:47:07PM +0800, kernel test robot wrote:
> > >    drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c: note: in included file:
> > > >> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h:1048:9: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected struct callback_head *head @@     got struct callback_head [noderef] __rcu * @@
> > >    drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h:1048:9: sparse:     expected struct callback_head *head
> > >    drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h:1048:9: sparse:     got struct callback_head [noderef] __rcu *
> > > >> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h:1048:9: sparse: sparse: cast removes address space '__rcu' of expression
> > ...
> > >   1045	
> > >   1046	static inline void arm_smmu_domain_free(struct arm_smmu_domain *smmu_domain)
> > >   1047	{
> > > > 1048		kfree_rcu(smmu_domain->invs, rcu);
> > 
> > Looks like it should be:
> >  static inline void arm_smmu_domain_free(struct arm_smmu_domain *smmu_domain)
> >  {
> > -       kfree_rcu(smmu_domain->invs, rcu);
> > +       struct arm_smmu_invs *invs = rcu_dereference(smmu_domain->invs);
> 
> rcu_derference_protected(,true) since we know there is no concurrency
> here..

Oh right, it's outside rcu_read_lock().

Thanks
Nicolin