Re: Bug#584846: Detects only 64MB and fails to boot on Intel Green City board if e820 hooked by GRUB2

H. Peter Anvin
2010-06-22T06:07:54Z

On 06/21/2010 10:22 PM, Josh Triplett wrote:
>
> How might I diagnose this further? What might cause Linux to refuse to
> use the e820 and e801 results provided by GRUB, but accept the ones
> provided by the BIOS?
>

This is interesting... you apparently have a ACPI 3-style e820 BIOS as
evidenced by the [1] markers, but Grub presents it as legacy style.
Now, the kernel shouldn't care, but this at least gives a clue.

Something that might be worthwhile is to add printf's to the kernel's
e820-parsing routine (in arch/x86/boot/e820.c) and figure out why it
doesn't like the output. It's a bit strange that meminfo would produce
sensible-looking output (well, legal, at least; presenting a two-byte
range is rather beyond crazy, and so forth) and the kernel wouldn't
accept it, as the code is intentionally very similar.

-hpa

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.