What else went on? See below.
Systemd, Linux, AMD and shoddy randomness
File this one under bad situations that probably don’t affect anyone.
It reemerged that some older generation AMD processors fail to generate random numbers in hardware after waking up from suspend, which has knock on effects into Systemd on Linux.
The bug is down to the fact that the software stack relies on the CPU’s RDRAND instruction to generate random ID numbers, but this instruction fails to work properly, returning an error code, on older AMD chips after the machine wakes up from suspend. The end result is the computer can’t suspend again after waking up until the box is rebooted.