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Date: Tue, 15 Jun 2010 08:44:19 +0200
From: Andi Kleen <andi@firstfloor.org>
To: Tony Luck <tony.luck@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>,
       "Eric W. Biederman" <ebiederm@xmission.com>,
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Subject: Re: Hardware Error Kernel Mini-Summit
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> There was a case mentioned at the collaboration summit
> meeting where a BIOS bug mis-reported whether ECC was
> enabled - claiming it was on, when in fact it was off.

Yes I heard about that, but since it's not a single bit setting
there are lots of different ways it could be broken in theory.

To check it you really need to have a tool that knows about
all the registers and checks them all.

It's a bit like checking if someone speaks a foreign language
by asking them a single question with a one letter answer.

> of the chipset specific code against each other. An EDAC
> driver that tells you that ECC is enabled might be lying too,
> if it is looking at the wrong bit or the wrong register.

Yep.

It's asking a question with a one word answer where you don't
know the correct answer.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only.