When I suspend while using kernel 5.8.x (currently 5.8.11), upon wakeup, my ethernet devices are unavailable. My motherboard has an Intel NIC, and an Aquantia 10GbE NIC, but the Intel one is the one that leads to the router. The 10GbE link goes directly to my server, with static IPs. I also can’t restart NetworkManager.service, as when I attempt to do so, the command just hangs. I can’t run “ip” commands like “ip addr” or “ip link”, they also just hang. The only thing I can do is hard reset my PC.
However, when running kernel 5.7.19, I don’t have any issues at all. I can suspend and resume just fine, no network issues at all.