And because its called only once, it does not need to be marked __init()
and must be kept around forever, right?
This is because every other architecture implements read_boot_clock64()
without __init: arm, s390. Beside, the original weak stub does not have __init
macro. So, I can certainly try to add it for x86, but I am not sure what is
the behavior once __init section is gone, but weak implementation stays.
And what about fixing that everywhere?