Re: 2.6.39-rc5-git2 boot crashs

From: Ingo Molnar
Date: Tue May 03 2011 - 16:51:13 EST



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

> On 05/03/2011 01:17 PM, Linus Torvalds wrote:
> >
> > That said, I don't really see why ELAN would be so special.
> >
>
> ELAN used to have a nonstandard A20 enabling sequence, until someone
> found out that changes to the mainline sequence had made ELAN work as a
> side effect.
>
> At this point, it's just a CPU selection thing, so it makes very little
> sense.

the ELAN .config option influences the following details:

- sets X86_L1_CACHE_SHIFT to 4 (16 bytes) instead of the typical 6 (64 bytes)
- sets X86_ALIGNMENT_16
- sets the -march=i486 compiler flag

So in terms of the kernel image it seems to be mostly equivalent to selecting
i486 from the CPU menu - except the X86_ALIGNMENT_16 detail (which does not
seem to do anything substantive, AFAICS).

Thanks,

Ingo
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