Dynamically setting new modes via framebuffer

Hi,

What's the standard framebuffer (driver) behavior for when a
fbdev-based application is already running (so mode set, framebuffer
alreay mapped) and the user attempts to set a new mode using fbset
(without the first application knowing about it)?

Should the driver deny it and e.g. return -EBUSY? Is the interface
simply permissive about that? Then how could the application get
notifications about mode change and adjust its rendering parameters?

Regards,
Ilyes

P.S: please CC me as I'm not registered with the mailing-list.