Re: [Patch] x86, x86_64: fix cpu model for family 0x6

[Petr Vandrovec]

Siddha, Suresh B wrote:
> Andi, please pickup this patch and push to Andrew/Linus.
>
> thanks,
> suresh
>
> --
> According to cpuid instruction in IA32 SDM-Vol2, when computing cpu model,
> we need to consider extended model ID for family 0x6 also.
>
> Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
>
> --- linux-2.6.14-rc2-git7/arch/i386/kernel/cpu/common.c~	2005-09-29 17:44:12.030688920 -0700
> +++ linux-2.6.14-rc2-git7/arch/i386/kernel/cpu/common.c	2005-09-29 17:44:30.967810040 -0700
> @@ -233,10 +233,10 @@ static void __init early_cpu_detect(void
>  		cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
>  		c->x86 = (tfms >> 8) & 15;
>  		c->x86_model = (tfms >> 4) & 15;
> -		if (c->x86 == 0xf) {
> +		if (c->x86 == 0xf)
>  			c->x86 += (tfms >> 20) & 0xff;
> +		if (c->x86 == 0x6 || c->x86 == 0xf)

Are you sure this is correct?  You just incremented c->x86 by extended
family, so I believe test should be

                if (c->x86 == 0x6 || c->x86 >= 0xf)

or maybe just

                if (c->x86 >= 0x6)

as chips with family 7..14 will either never appear, or they'll follow
existing rules (I believe all chips ever built return upper bits of tfms
zeroed, so maybe we could get rid of all these 'if' completely).
						Petr Vandrovec

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/