Re: Cyrix VSPM Patches for 2.1.62

B. James Phillippe (bryan@Terran.ORG)
Sat, 8 Nov 1997 16:36:41 -0800 (PST)


On Mon, 3 Nov 1997, Christoph Lameter wrote:

> I found the Cyrix VSPM patches for 2.1.39. They were difficult to handle
> since they were based on RCS. Here they come adapted for 2.1.62 in regular
> customary diff format:

> +#if !defined(__SMP__) && defined(CONFIG_CYRIX_6X86_NOLOCK)
> + getCx86($0xc1) # CCR1 |= NO_LOCK
> + orb $0x10,%ax
> + movb %ax,%bx
> + setCx86($0xe8,%bx)
> +#endif

This is wrong, I think. Shouldn't the line setCx86($0xe8,%bx) read
setCx86($0xc1,%bx)? I just sent a message noting this typo WRT the posted
Cyrix 6x86 attack. Having this fix in the patch (or using set6x86 to turn
off locked cycles) successfully defends against the attack.

cheers,
-bp

--
B. James Phillippe <bryan@Terran.ORG>
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