Re: Reserving physical memory at boot time

["H. Peter Anvin" <hpa@zytor.com>]

Followup to:  <32981.4.64.238.61.1046844111.squirrel@www.osdl.org>
By author:    "Randy.Dunlap" <rddunlap@osdl.org>
In newsgroup: linux.dev.kernel
> 
> OK, with feeling:
> 
> I agree with you since the boot protocol is well-defined.
> 
> Just to be clear, my comment was referring to
> Documentation/kernel-parameters.txt, not to any C code.
> 
> And it would really be helpful to catch issues like this soon
> after they happen...
> 

Unfortunately last time I commented on this the response was roughly
"well, the patch already made it into Linus' kernel, it's too late to
fix it now."  That isn't exactly a very helpful response.

The mem= parameter has the semantic in the i386/PC boot protocol that
it specifies the top address of the usable memory region that begins
at 0x100000.  It's a bit of a wart that the boot loaders have to be
aware of this, but it's so and it's been so for a very long time.

	-hpa

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