RE: [PATCH v3 2/4] iommu/vt-d: Check domain force_snooping against attached devices

[Tian, Kevin]

> From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Sent: Friday, May 6, 2022 1:27 PM
> +
> +/*
> + * Set the page snoop control for a pasid entry which has been set up.
> + */
> +void intel_pasid_setup_page_snoop_control(struct intel_iommu *iommu,
> +					  struct device *dev, u32 pasid)
> +{
> +	struct pasid_entry *pte;
> +	u16 did;
> +
> +	spin_lock(&iommu->lock);
> +	pte = intel_pasid_get_entry(dev, pasid);
> +	if (WARN_ON(!pte || !pasid_pte_is_present(pte))) {
> +		spin_unlock(&iommu->lock);
> +		return;
> +	}
> +
> +	pasid_set_pgsnp(pte);
> +	did = pasid_get_domain_id(pte);
> +	spin_unlock(&iommu->lock);
> +
> +	pasid_flush_caches(iommu, pte, pasid, did);
> +}

The comment of pasid_flush_caches() says:

/*
 * This function flushes cache for a newly setup pasid table entry.
 * Caller of it should not modify the in-use pasid table entries.
 */

Can you check whether that comment still hold?