On 2023/8/1 15:03, Tian, Kevin wrote:
/** * iommu_device_use_default_domain() - Device driver wants to handle device * DMA through the kernel DMA API. @@ -3052,14 +3063,14 @@ int iommu_device_use_default_domain(struct device *dev) mutex_lock(&group->mutex); if (group->owner_cnt) { - if (group->owner || !iommu_is_default_domain(group) || - !xa_empty(&group->pasid_array)) { + if (group->owner || !iommu_is_default_domain(group)) { ret = -EBUSY; goto unlock_out; } } group->owner_cnt++; + assert_pasid_dma_ownership(group);Old code returns error if pasid_xrrary is not empty. New code continues to take ownership with a warning. this is a functional change. Is it intended or not?
If iommu_device_use_default_domain() is called with pasid_array not empty, there must be a bug somewhere in the device driver. We should WARN it instead of returning an error. Probably this is a functional change? If so, I can add this in the commit message. Best regards, baolu
