Re: [PATCH v4 09/10] iommu/arm-smmu-v3: Remove ASID/VMID from arm_smmu_domain

Jason Gunthorpe
2026-04-10T00:27:53Z

On Thu, Mar 19, 2026 at 12:51:55PM -0700, Nicolin Chen wrote:
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> index 846a278fa5469..0e48264ccd01b 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> @@ -300,14 +300,6 @@ static void arm_smmu_sva_domain_free(struct iommu_domain *domain)
> */
> arm_smmu_domain_inv(smmu_domain);
>
> - /*
> - * Notice that the arm_smmu_mm_arch_invalidate_secondary_tlbs op can
> - * still be called/running at this point. We allow the ASID to be
> - * reused, and if there is a race then it just suffers harmless
> - * unnecessary invalidation.
> - */
> - xa_erase(&arm_smmu_asid_xa, smmu_domain->cd.asid);
> -

I don't think this artifact has disappeared so the comment should
probably remain too. It has become slightly different because it is
now running under RCU protections so it will clear alot faster.

Otherwise

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Jason