linux-kernel - Re: [PATCH 4/4] x86: Detect model/family mismatches for common microcode revision

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Message-ID: <20120614180202.GD13629@x1.osrc.amd.com>
Date:	Thu, 14 Jun 2012 20:02:02 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Andi Kleen <andi@...stfloor.org>
Cc:	x86@...nel.org, linux-kernel@...r.kernel.org, eranian@...gle.com,
	peterz@...radead.org, Andi Kleen <ak@...ux.intel.com>
Subject: Re: [PATCH 4/4] x86: Detect model/family mismatches for common
 microcode revision

On Wed, Jun 13, 2012 at 01:20:42PM -0700, Andi Kleen wrote:
> From: Andi Kleen <ak@...ux.intel.com>
> 
> When the model/family don't match force the common microcode to zero.
> On such configurations there is no sane way to check for microcode
> revisions, so don't even try.
> 
> Signed-off-by: Andi Kleen <ak@...ux.intel.com>
> ---
>  arch/x86/kernel/cpu/common.c |   26 ++++++++++++++++++++------
>  1 files changed, 20 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
> index cfc50e0..9642929 100644
> --- a/arch/x86/kernel/cpu/common.c
> +++ b/arch/x86/kernel/cpu/common.c
> @@ -1183,12 +1183,26 @@ __cpuinit void boot_update_min_microcode(struct cpuinfo_x86 *c)
>  	if (!boot_min_microcode) {
>  		boot_min_microcode = c->microcode;
>  		boot_cpu_data.microcode = c->microcode;
> -	} else if (c->microcode < boot_min_microcode) {
> -		pr_warn("CPU %d has lower microcode revision %x at boot than boot CPU (%x)\n",
> -			smp_processor_id(), 
> -			c->microcode,
> -			boot_min_microcode);
> -		boot_cpu_data.microcode = c->microcode;
> +	} else {
> +		if (c->microcode < boot_min_microcode) {
> +			pr_warn("CPU %d has lower microcode revision %x at boot than boot CPU (%x)\n",
> +				smp_processor_id(), 
> +				c->microcode,
> +				boot_min_microcode);
> +			boot_cpu_data.microcode = c->microcode;
> +		}
> +		/* Assume steppings have common microcode version numbers */
> +		if (c->x86 != boot_cpu_data.x86 || 


Apply? [y]es/[n]o/[e]dit/[v]iew patch/[a]ccept all y
Applying: x86: Detect model/family mismatches for common microcode revision
/home/boris/kernel/.git/rebase-apply/patch:22: trailing whitespace.
                                smp_processor_id(), 
/home/boris/kernel/.git/rebase-apply/patch:28: trailing whitespace.
                if (c->x86 != boot_cpu_data.x86 || 
warning: 2 lines add whitespace errors.

-- 
Regards/Gruss,
Boris.
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