Subject: Re: [PATCH 2/2] x86/microcode/intel: Extend BDW late-loading with
 platform id and LLC check
To: Borislav Petkov <bp@alien8.de>
References: <1515995003-113069-1-git-send-email-zhang.jia@linux.alibaba.com>
 <1515995003-113069-3-git-send-email-zhang.jia@linux.alibaba.com>
 <20180115101016.k4ksjlclufogcfrt@pd.tnic>
Cc: tony.luck@intel.com, mingo@redhat.com, hpa@zytor.com,
        tglx@linutronix.de, x86@kernel.org, linux-kernel@vger.kernel.org
From: Jia Zhang <zhang.jia@linux.alibaba.com>
Message-ID: <31061762-96f4-0cf7-077a-56c422088bea@linux.alibaba.com>
Date: Mon, 15 Jan 2018 21:06:07 +0800
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Yes I'm wrong with platform id so drop it.

Jia

在 2018/1/15 下午6:10, Borislav Petkov 写道:
> On Mon, Jan 15, 2018 at 01:43:23PM +0800, Jia Zhang wrote:
>> The commit b94b73733171
>> ("x86/microcode/intel: Extend BDW late-loading with a revision check")
>> reduces the impact of erratum BDF90 for Broadwell process model. Now,
>> the impact can be reduced further through adding the checks for
>> platform id and the size of LLC per core.
>>
>> This fix is useful to reduce the impact for microcode update launched
>> by BIOS with a must machine reset.
>>
>> For more details, see erratum BDF90 in document #334165 (Intel Xeon
>> Processor E7-8800/4800 v4 Product Family Specification Update) from
>> September 2017.
> 
> You must be looking at something NDA or so but this:
> 
> https://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-e7-v4-spec-update.pdf
> 
> doesn't have none of that
> 
>> +         llc_size_per_core(c) > 2621440 &&
>> +         c->platform_id == 0xef &&
> 
> fun.
>