iommu/amd: Wait for completion of IOTLB flush in attach_device

To make sure the domain tlb flush completes before the
function returns, explicitly wait for its completion.

Signed-off-by: Filippo Sironi <[email protected]>
Fixes: 42a49f9 ("amd-iommu: flush domain tlb when attaching a new device")
[joro: Added commit message and fixes tag]
Signed-off-by: Joerg Roedel <[email protected]>

Author: filipposironi

drivers/iommu/amd_iommu.c

@@ -2212,6 +2212,8 @@ static int attach_device(struct device *dev,
 	 */
 	domain_flush_tlb_pde(domain);
 
+	domain_flush_complete(domain);
+
 	return ret;
 }