RE: [PATCH v2 6/7] iommu/arm-smmu-v3: Introduce master->ats_broken flag

Tian, Kevin
2026-03-18T07:40:01Z

> From: Nicolin Chen <nicolinc@nvidia.com>
> Sent: Wednesday, March 18, 2026 3:16 AM
>
> @@ -3060,6 +3079,14 @@ static bool arm_smmu_ats_supported(struct
> arm_smmu_master *master)
> if (!(fwspec->flags & IOMMU_FWSPEC_PCI_RC_ATS))
> return false;
>
> + /*
> + * Reject any new ATS request because ATC invalidation was timed
> out.
> + * The PCI device should go through a recovery (reset) and notify the
> + * SMMUv3 driver via a reset_device_done callback.
> + */
> + if (READ_ONCE(master->ats_broken))
> + return false;
> +

"Reject any new ATS request" means any new request to enable ATS
on this device, instead of rejecting any new ATS translation request,
correct? next patch does the actual work to block ATS...