i have come across this situation, but since most of the times there is an actual object supposed to emmit the light from the area light, the problem isn't visible. I would recommend either using another type of light or moving the area light away from the ceiling. Nevertheless, I'm curious to see if there is an actual workaround for this issue.
Somebody help me~~~~~how can i get rid of the sky portal`s shadow
I am facing the exact same problem all the time. Just now, I found out what christopher said here was right! Positioning the light very close to the surface on its back (the ceiling in this example) worked! But its not really a prefect solution as I still get a slight amount of shadow near the middle. Anyone knows an even better solution?