Where knives and forks are laid is up for discussion (2,3,5)
I believe the answer is:
on the table
'up for discussion' is the definition.
(something on the table is being discussed)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for on the table that I've seen before include "Where to lay out fighting irons" , "open for discussion" .)