Re: [PATCH] x86/boot: Reorganize and clean up the BIOS area reservation code

From: Ingo Molnar
Date: Thu Jul 21 2016 - 05:14:21 EST

* H. Peter Anvin <hpa@xxxxxxxxx> wrote:

> We already reserve the first megabyte by default. There is something really bizarre about this; the bug report simply doesn't seem to make any sense.

Btw., are you sure about this? We do reserve the first 64KB:

config X86_RESERVE_LOW
int "Amount of low memory, in kilobytes, to reserve for the BIOS"
default 64
range 4 640
Specify the amount of low memory to reserve for the BIOS.

But I cannot find the place that allocates the first 1MB.