The following is from the head of Machon Shilo, Rabbi David Bar-Hayim:
My recommendation is not to participate in the levaya of HaGaon HaGadol Rav Chaim Kanievsky ztz"l. The essential reason is possible sakanat nefashot. Instead of participating in the levaya I recommend studying some Torah for half an hour during the course of the day. It is my intention to put something in writing on this matter in the coming days.