linux-kernel - Re: [PATCH] x86: Fix override new_cpu

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Date:	Thu, 27 Jun 2013 12:54:35 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Wang YanQing <udknight@...il.com>
Cc:	hpa@...or.com, tglx@...utronix.de, mingo@...hat.com,
	x86@...nel.org, bp@...e.de, fenghua.yu@...el.com,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] x86: Fix override new_cpu_data.x86 with 486

On Thu, Jun 27, 2013 at 12:26:40AM +0800, Wang YanQing wrote:
> 
> We should set X86 to 486 before use cpuid
> to detect the cpu type, if we set X86 to 486
> after cpuid, then we will get 486 for ever.

So not "for ever" but until cpu_detect runs.

> 
> Yes, we will correct this in early_cpu_init,
> but it is still a wrong behavior, right? So
> just fix it.

Right, so this patch is correct and it fixes the small window where we
run with family == 4 before cpu_detect but the commit message needs a
bit massaging before it gets applied.

> 
> I also find maybe we can delete the new_cpu_data,
> because we will over write all the information
> in early_cpu_init, and before early_cpu_init,
> there is no user of new_cpu_data, but this is
> another patch in the future.

You can drop that part.

Thanks.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
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