Output with patch applied:

Sep 12 12:08:20 zen kernel: kfd kfd: Allocated 3969056 bytes on gart
Sep 12 12:08:20 zen kernel: Topology: Add APU node [0x15dd:0x1002]
Sep 12 12:08:20 zen kernel: Failed to attache to group
Sep 12 12:08:20 zen kernel: amd_iommu_init_device failed: -22
Sep 12 12:08:20 zen kernel: kfd kfd: Failed to resume IOMMU for device
1002:15dd
Sep 12 12:08:20 zen kernel: Creating topology SYSFS entries
Sep 12 12:08:20 zen kernel: kfd kfd: device 1002:15dd NOT added due to errors

Full log attached.

Thank you
Marvin