Just ran across this article about Debian dealing with similar issues. https://daniel-lange.com/archives/152-hello-buster.html
One of the suggested work-arounds is to rely on virtio_rng on virtual machines, but it seems Guix already uses that on my machine, so perhaps it doesn’t help: rob@garp ~$ cat /sys/devices/virtual/misc/hw_random/rng_available virtio_rng.0 rob@garp ~$ cat /sys/devices/virtual/misc/hw_random/rng_current virtio_rng.0
