RE: [PATCH] x86: Use low memory size directly from Multiboot

[<dinhngoc.tu@xxxxxxx>]

> The comment here is a pretty clear indication that bad values may have been
> observed, even if this was only in the distant past. But we have to not
> regress even on very old boot loaders.
> 
> Is the kexec case recognizable by any means (including to distinguish kexec
> properly communicating the value vs it not doing so, as iirc it was said on 
> irc
> that this didn't always work correctly there), such that we could skip using
> the BDA value in that case?

Old Kexec used to report the value in bytes instead of kilobytes like it's 
supposed to. I can make a special case for that so that we won't have to rely 
on the BDA.