Unknown symbol qdm_iommu_unmap

Hi,
as per the getting started guide and the SR-IOV KVM guide, I have built QAT 1.7 successfully on Centos 7.
However, after what appeared to be successful installation, when it comes to loading of the driver and qat_service it gives this message:

Jul 12 00:02:48 localhost systemd: Reloading.
Jul 12 00:02:48 localhost kernel: QAT: Stopping all acceleration devices.
Jul 12 00:02:51 localhost kernel: QAT: invalid header 0x666f6d
Jul 12 00:02:51 localhost kernel: QAT: map SUOF failed
Jul 12 00:02:51 localhost kernel: c3xxx 0000:01:00.0: Failed to map FW
Jul 12 00:02:51 localhost kernel: c3xxx 0000:01:00.0: Failed to load acceleration FW
Jul 12 00:02:51 localhost kernel: c3xxx 0000:01:00.0: Resetting device qat_dev0
Jul 12 00:02:51 localhost kernel: c3xxx 0000:01:00.0: Function level reset
Jul 12 00:02:51 localhost kernel: c3xxx: probe of 0000:01:00.0 failed with error -14
Jul 12 00:02:52 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_unmap (err 0)
Jul 12 00:02:52 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_map (err 0)
Jul 12 00:02:52 localhost kernel: QAT: Stopping all acceleration devices.
Jul 12 00:03:16 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_unmap (err 0)
Jul 12 00:03:16 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_map (err 0)
Jul 12 00:03:28 localhost systemd: Starting Cleanup of Temporary Directories...
Jul 12 00:03:28 localhost systemd: Started Cleanup of Temporary Directories.
Jul 12 00:03:34 localhost kernel: nvme nvme0: async event result 00020001
Jul 12 00:03:51 localhost kernel: usdm_drv: module_layout: kernel tainted.
Jul 12 00:03:51 localhost kernel: Disabling lock debugging due to kernel taint
Jul 12 00:03:51 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_unmap (err 0)
Jul 12 00:03:51 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_map (err 0)

service qat_service start gives this:

Jul 11 22:51:31 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_unmap (err 0)
Jul 11 22:51:31 localhost kernel: usdm_drv: Unknown symbol qdm_iommu_map (err 0)
Jul 11 22:51:31 localhost qat_service: Stopping all devices.
Jul 11 22:51:31 localhost kernel: QAT: Stopping all acceleration devices.
Jul 11 22:51:31 localhost qat_service: Starting all devices.
Jul 11 22:51:31 localhost qat_service: Checking status of all devices.
Jul 11 22:51:31 localhost qat_service: There is 0 QAT acceleration device(s) in the system:

any pointers much appreciated.