[$] What to do in response to a kernel warning

The kernel provides a number of macros internally to allow code to generate
warnings when something goes wrong. It does not, however, provide a lot of
guidance regarding what should happen when a warning is issued. Alexander
Popov recently posted a
patch series adding an option for the system's response to warnings;
that series seems unlikely to be applied in anything close to its current
form, but it did succeed in provoking a discussion on how warnings should
be handled.