From: "Kani, Toshimitsu" <toshi.kani@hpe.com>
To: "bp@alien8.de" <bp@alien8.de>
CC: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "mchehab@s-opensource.com" <mchehab@s-opensource.com>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
        "mchehab@kernel.org" <mchehab@kernel.org>,
        "rjw@rjwysocki.net" <rjw@rjwysocki.net>,
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        <srinivas.pandruvada@linux.intel.com>,
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        "lenb@kernel.org" <lenb@kernel.org>,
        "linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>,
        "linux-edac@vger.kernel.org" <linux-edac@vger.kernel.org>
Subject: Re: [PATCH 3/3] ghes_edac: add platform check to enable ghes_edac
Thread-Topic: [PATCH 3/3] ghes_edac: add platform check to enable ghes_edac
Thread-Index: AQHS/0lGOl4i5ss6QUSn88C0VF1rJqJZF6OAgADnxYCAABgPgIABQtCAgADJ5ACAAP1sAA==
Date: Thu, 20 Jul 2017 19:50:03 +0000
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On Thu, 2017-07-20 at 06:33 +0200, Borislav Petkov wrote:
> On Wed, Jul 19, 2017 at 04:40:25PM +0000, Kani, Toshimitsu wrote:
> >  ghes_edac allows to report errors to OS management tools like
> > rasdaemon in addition to platform- specific managements.
> 
> So ghes_edac *is* a poor man's driver in the sense that it doesn't do
> anything fancy but repeat like a parrot data it has gotten from the
> firmware and shoving it into the EDAC counters. At least that's the
> intention. Nothing more. 

Right for ghes_edac.

> All the action stuff like error detection and recovery should be done
> by the firmware.

GHES / firmware-first still requires OS recovery actions when an error
cannot be corrected by the platform.  They are handled by ghes_proc(),
and ghes_edac remains its error-reporting wrapper.

> But considering how SNAFU'd firmware is, I wouldn't expect any great
> RAS functionality there. Of course, I'd be delighted to be proven
> wrong.

Firmware has better knowledge about the platform and can provide better
RAS when implemented properly.  I agree that user experiences may vary
on platforms.

Thanks,
-Toshi