Re: [PATCH 0/6] Boot-time switching between 4- and 5-level paging for 4.15, Part 1

[Ingo Molnar]

* Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> wrote:

> > Or, could we keep MAX_PHYSMEM_BITS constant, and introduce a _different_ constant 
> > that is dynamic, and which could be used in the cases where the 5-level paging 
> > config causes too much memory footprint in the common 4-level paging case?
> 
> This is more labor intensive case with unclear benefit.
> 
> Dynamic MAX_PHYSMEM_BITS doesn't cause any issue in waste majority of
> cases.

Almost nothing uses it - and even in those few cases it caused problems.

Making a variable that 'looks' like a constant macro dynamic in a rare Kconfig 
scenario is asking for trouble.

Thanks,

	Ingo