Re: 2.6.22-rc1 does not boot on VIA C3_2 cause of X86_CMPXCHG64

[Linus Torvalds <torvalds@linux-foundation.org>]

On Thu, 17 May 2007, Christian wrote:
>
> my small VIA C3_2 box does not boot with 2.6.22-rc1.
> It even does not uncompress the kernel.
> 
> The configuration as M386 M486 works. But M586 + MVIAC3_2
> does not work.

Ahh, from the EPIA HOWTO:

	13.2. Is the C3 Pentium compatible?

	Yes. But Samuel 2, Ezra, Ezra T C3 processors have a problem with 
	the cmpxchg8b (i.e. CMOV) opcode. Nehemiah and Antaur processors 
	are not affected.

However, that would imply that you don't have a VIA C3-2 (Nehamiah) at 
all, but the older original CyrixIII/VIA C3.

Can you check? The Nehemian (C3-2) should be model 9 or greater.

So afaik, you should use MCYRIXIII, and make _that_ be the one that 
disables the use of the cmpxchg8b instruction.

Can you please verify?

		Linus
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