On 2023/12/14 10:55, Yang, Weijiang wrote:
On 11/27/2023 2:34 PM, Yi Liu wrote:
From: Lu Baolu baolu.lu@linux.intel.com
This allows the upper layers to set a nested type domain to a PASID of a device if the PASID feature is supported by the IOMMU hardware.
The set_dev_pasid callback for non-nest domain has already be there, so this only needs to add it for nested domains.
Signed-off-by: Lu Baolu baolu.lu@linux.intel.com Signed-off-by: Yi Liu yi.l.liu@intel.com
drivers/iommu/intel/nested.c | 47 ++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+)
diff --git a/drivers/iommu/intel/nested.c b/drivers/iommu/intel/nested.c index 44ad48db7ea0..f6f687750104 100644 --- a/drivers/iommu/intel/nested.c +++ b/drivers/iommu/intel/nested.c @@ -68,6 +68,52 @@ static int intel_nested_attach_dev(struct iommu_domain *domain, return 0; } +static int intel_nested_set_dev_pasid(struct iommu_domain *domain, + struct device *dev, ioasid_t pasid) +{ + struct device_domain_info *info = dev_iommu_priv_get(dev); + struct dmar_domain *dmar_domain = to_dmar_domain(domain); + struct intel_iommu *iommu = info->iommu; + struct dev_pasid_info *dev_pasid; + unsigned long flags; + int ret = 0;
+ if (!pasid_supported(iommu)) + return -EOPNOTSUPP;
+ if (iommu->agaw < dmar_domain->s2_domain->agaw) + return -EINVAL;
+ ret = prepare_domain_attach_device(&dmar_domain->s2_domain->domain, dev); + if (ret) + return ret;
+ dev_pasid = kzalloc(sizeof(*dev_pasid), GFP_KERNEL); + if (!dev_pasid) + return -ENOMEM;
+ ret = domain_attach_iommu(dmar_domain, iommu); + if (ret) + goto err_free;
+ ret = intel_pasid_setup_nested(iommu, dev, pasid, dmar_domain); + if (ret) + goto err_detach_iommu;
+ dev_pasid->dev = dev; + dev_pasid->pasid = pasid; + spin_lock_irqsave(&dmar_domain->lock, flags); + list_add(&dev_pasid->link_domain, &dmar_domain->dev_pasids); + spin_unlock_irqrestore(&dmar_domain->lock, flags);
---> list_add(&dev_pasid->link_domain, &dmar_domain->dev_pasids);
dev_pasid is linked at later time, this leads to domain->has_iotlb_device is not correctly set, which finally results into a missing of device iotlb flush in iommu_flush_dev_iotlb()when it's called. Check this call path: domain_attach_iommu()->domain_update_iommu_cap()->domain_update_iotlb()->domain->has_iotlb_device = has_iotlb_device; The ugly fixup is to call domain_update_iommu_cap() or domain_update_iotlb() here again before return. The similar issue is in intel_iommu_set_dev_pasid() and intel_nested_attach_dev().
Yes, domain->has_iotlb_device must be updated whenever a domain is attached to (or removed from) a RID or PASID. I would be grateful if you could post some patches to fix the set_device_pasid and nested_attach_dev paths.
I assume Yi can fix this series in the next version.
Best regards, baolu