Crying on the walls of Kaaba

Hy. I know there are many discussions about why muslim kiss black stone or why muslim pray towards kaba but i think my question is different i.e why Muslims hug the walls of Kaba and cry with their whole body against the wall of kaba as it can be seen in this and this and this picture? about kissing the black stone, there is a report from a sahabi saying 'i wouldnt have kissed you if I've not seen the Prophet do it', but what is the evidence (did Prophet do it or any Sahabi) of the acts shown in the pictures above? thank you.