KVM guest cannot use TPM after upgrade to Fedora 31

For some time I have been using my laptop’s TPM 2.0 device from my Windows guest by passing it through to the VM (exclusively). In order to do that I had to always stop the tpm2-abrmd service before starting the guest. This has worked with at least with Fedora 29 and 30.

Since I upgraded to Fedora 31 this is no longer working. When I start the guest, I get the following error message: libvirt.libvirtError: internal error: child reported (status=125): unable to open /dev/tpm0: Device or resource busy

I cannot see that there is anything that is using the /dev/tpm0 device at this point. Of course I have stopped the tpm2-abrmd service.

Has anyone else seen this? Any suggestions?