linux-kernel - Re: [PATCH 3/5] x86/mcheck/AMD: Reduce number of blocks scanned per bank

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Date:	Thu, 14 Jan 2016 16:48:22 -0600
From:	Aravind Gopalakrishnan <aravind.gopalakrishnan@....com>
To:	Borislav Petkov <bp@...en8.de>
CC:	<tony.luck@...el.com>, <tglx@...utronix.de>, <mingo@...hat.com>,
	<hpa@...or.com>, <x86@...nel.org>, <linux-edac@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 3/5] x86/mcheck/AMD: Reduce number of blocks scanned per
 bank

On 1/14/2016 4:37 PM, Borislav Petkov wrote:
> On Thu, Jan 14, 2016 at 04:05:38PM -0600, Aravind Gopalakrishnan wrote:
>>   
>> -#define NR_BLOCKS         9
>> +#define NR_BLOCKS         5
> This doesn't look necessary to me. We do check MCi_MISC[BlkPtr] before
> accessing that MSR.
>

True. But that BlkPtr logic also will undergo changes as it's 
interpretation for future processors is different.

We are guaranteed to have all the MISC registers (all 5 of them) going 
forward.
But we shouldn't be accessing MSRs beyond the 5th extended MISC register 
for each bank as that is the architectural boundary.
Hence the change here.

Thanks,
-Aravind.