As Slab said, and a leak-down test could confirm its likeliness. The nose will tell you too. Walk back and give a sniff of the smoke, but a ways back. It has a sweetish smell, different than oil. Best explanation I've heard for the infamous mosquito fogger start up on Goldwing is that sooner or later the piston ring edges all align on the bottom and residual oil left on the cylinder walls finds its way into the combustion chamber by gravity. This can be worse when left on the side stand. I have made it a habit to turn the bike off sitting upright, take off helmet and gear, then lean the bike right as far as you dare for a few seconds. The hot oil in the left cylinders will quickly run to the crankcase. Then put the bike on the side stand to the left and it will drain the right cylinders. As long as I do this, it doesn't smoke. Oil should smoke a little bluer than coolant.
If it was a cool morning, it may be a cause of the longer "smoke" at startup too. Replacing head gaskets isn't too bad on these and might give you peace of mind on trips.