On 2023/8/2 9:39, Tian, Kevin wrote:
From: Baolu Lu<baolu.lu@xxxxxxxxxxxxxxx>
Sent: Tuesday, August 1, 2023 3:44 PM
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.
IMHO we should WARN*and* return an error.
Okay, fine to me. Will make this in the next version.
Best regards,
baolu
