Comment 8 for bug 1450396

OK, then it might be one of the other hooks in /usr/lib/pm-utils/sleep.d that pm-suspend runs. According to your dmesg it's unlikely that you have the "alx" module loaded ("lsmod | grep alx" should be empty).

Can you please attach your /var/log/pm-suspend.log?

60_wpa_supplicant could be a likely cause -- can you see if this works:

  sudo wpa_cli suspend ; sudo systemctl suspend; sudo wpa_cli resume

75modules is a less likely cause, I'll see if that does anything on your system in pm-suspend.log. The other hooks seem rather unlikely to me, so let's check these two first.