Comment # 3 on bug 1092668 from Takashi Iwai

Now reading back your description, I understand what you meant.
It's likely about the hibernation failure due to some kernel driver (or PM
core) issue.  It should be mentioned better in kernel messages.

So, please attach the whole kernel messages (dmesg output), not only some
snippet.  The r8169 message can be a side-effect, not the cause.

Also, for testing the hibernate, you can run like
  systemctl hibernate

Or the direct method would be to write
  echo disk > /sys/power/state
as root.